Ever since this country voted in resounding opposition to its fading armed forces government last November, military authority has been quietly shoving Uruguayan politics away from public view.

Outdoor meetings are no longer permitted, and the signs that marked the headquarters of political party movements have been ordered removed. The progovernment newspapers have shuffled politics to the back pages and last month a magazine was shut down for interviewing a leading conservative politician.

Uruguay's generals speak much now of maintaining order. In November, the government carried out a major step of its promised democratic opening by permitting the first political party primary elections in 10 years of authoritarian rule. The result was overwhelming majorities for antigovernment slates, and night-long celebrations in Montevideo's tree-lined streets.

Now, very methodically, the generals are seeking to slow the democratic momentum.

"Liberty is what is excessive" in Uruguay, said Interior Minister Gen. Yamandu Trinidad recently. "The armed forces have tried by all means to provide liberty and have been too broad."

The crossed political currents of this hot Uruguayan summer define one of the most delicate of the democratic movements emerging in southern South America. Surrounded by Brazil and Argentina and politically reflective of both, Uruguay appears to be teetering between its own democratic traditions and the region's lingering creed of institutional military rule.

Military leaders here have promised to inaugurate a civilian government in early 1985, following an elaborately scheduled process of internal party reorganization, military-civilian negotiations, constitutional revision and general elections.

The first of these steps, including November's election of delegates to party conventions, has prompted the leadership of Uruguay's traditional parties to resurface nearly intact after a decade of enforced inactivity.

Propelled by widespread discontent with failed economic policies and led by the military's harshest critics, the party leaderships now expect to return the country to much the same government and policies that were disrupted by terrorism and then overturned by the military in 1973.

For many Uruguayans, their democratic past is the great pride of this country the size of North Dakota often overlooked among South America's giants. Governed by progressive democratic governments for most of the 20th century, Uruguay introduced such reforms as women's suffrage and the eight-hour workday before many nations in Europe. With the wealth of its cattle and sheep ranches, it constructed the most advanced welfare state in Latin America.

"We are not like these other countries here, with the coups and the dictators," indignantly insisted one party leader, Juan Pivel DeVoto. "We have always been the most advanced, until what happened to us in 1973. That was a historical accident."

Military leaders, in contrast, see the past governments as ineffectual and elitist, and have hoped to install a new model of limited democracy drawn from the right-wing military ideologies of the 1970s. Civilian government by this plan would include strict limits on democratic participation, prohibition of leftist parties and an institutionalized role for the armed forces in all future governments.

Few politicians and diplomats here now believe the military will achieve all it wants, for the new restrictions need the support of political leaders.

"Even the military doesn't want all that they planned before," said Jorge Batlle, a former presidential candidate and leader of the centrist Colorado party. "They know it can't work for them now."

The question of just how Uruguay's next government is elected and structured has become the crucial issue for both the military and the reemergent political parties and a principal motive for the continuing shows of repression by the government, political leaders say.

Beginning in March, military leaders and committees elected by the three newly reactivated political parties are scheduled to begin negotiating the changes in Uruguay's constitution sought by the military and the handling of military government corruption and human rights violations.

Party leaders, although willing to compromise on such issues as human rights, intend to demand a lifting of the outstanding restrictions on leftist parties and about 1,000 politicians still prohibited from activity, including top leaders of the traditional Colorado (Red) and Blanco (White) parties.

"The process is at a delicate stage," a diplomat here said. "This is a place where the institutional boundaries were broken down, and the military rolled in and absorbed the responsibilities of the parties. The problem could now be viewed as where the frontiers will be built up again."

Each side has begun maneuvering for position. "There is a test here of whether the move to democracy is being led by the military, or forced by the opposition," said Javier Fernandez, an editor of the opposition magazine Opinar. "The government feels it has to prove that it is in control, to balance the loss of the elections."

So far, while the government has dictated the timetable and form of the democratic opening, its decision to give up power has appeared to be anything but voluntary.

Politically unlearned and often inarticulate, Uruguay's military leaders have had difficulty explaining their mission in government, and for years refused to admit publicly that there had even been a coup.

The government borrowed much of the policy and politics of military governments in Brazil, Chile and Argentina, where ideologists envisioned the transformation of political, economic and cultural life with vaguely defined anticommunist and conservative Christian values.

The military government moved forcefully against Uruguay's left-of-center politicians, trade union movement and suspected supporters of the urban guerrillas, and by the late 1970s Uruguay was often cited as having the highest per capita level of political prisoners in the world.

International human rights groups estimated that most of those arrested were tortured, and many hundreds died under interrogation. Currently, just under 1,000 political prisoners remain in Uruguayan jails. Although there have been no recent reports of death or torture, many are being held without charges or have not been released after the end of their sentences, according to diplomats and opposition sources.

The turning point of this harsh rule came in 1980, when the armed forces sought to institutionalize their absolute power while offering limited democracy through a new constitution, only to suffer a remarkable defeat in a plebiscite.

Six months of official silence and political confusion followed the constitution's unexpected defeat. Finally, as the government's conservative economic model began to collapse during 1981, military officials announced the new political plan, including general elections in November 1984 and a new plebiscite on a negotiated constitution.

Since then, as economic conditions and the government's political popularity have deteriorated, the military's public insistence on its institutional plans has grown increasingly vague.

"It is up to us now to take the initiative," said Bernardo Berro of the Blanco party. "Until now the parties have been in a more passive position. The military has proposed and we have accepted or rejected. We have accomplished something by repoliticizing the Uruguayan climate, but we still have much to win back."