U.S. Assistant Secretary of State Chester Crocker will meet a high-level South African delegation in Zurich Monday to discuss amendments to a United Nations plan for independence of the Pretoria-administered territory of Namibia, the State Department announced today in Washington.

Those amendments foresee a specific timetable for implementing the U.N. plan, which is to culminate in Namibian independence in January 1983, as well as a proposal that soldiers of the five Western nations that drew up the plan form the bulk of a U.N. peacekeeping force, the Afrikaans-language newspaper Beeld reported today.

Beeld, which has close ties to South Africa's ruling National Party, disclosed the Zurich meeting that was announced later in the day by the State Department.

The meeting is "to provide South Africa with clarifications they requested on points concerning the basis for moving forward in the Namibian negotiations," a State Department official, reached by telephone, said.

The United States, Britain, France, West Germany and Canada have labored for more than four years to get a U.N.-supervised election in Namibia, or Southwest Africa. They are to meet again Thursday in New York to discuss the latest plan.

South Africa has ruled Namibia since 1920 under an old League of Nations mandate withdrawn in 1976 by the United Nations, which considers Pretoria's presence there illegal.

A State Department official declined to comment on specifics of what will be discussed in Zurich or on Beeld's account, which is the fullest to date, of the amendments being offered by the United States and its allies to get South Africa's cooperation with the U.N. plan.

A Western diplomatic source here said Beeld's account generally is accurate. It reported that the plan's amendments have the endorsement, in principle, of South Africa and of the African states that support the Southwest Africa People's Organization (SWAPO) battling for control of Namibia.

Angola's agreement was secured after West German Foreign Minister Hans-Dietrich Genscher met with his Angolan counterpart, Paulo Jorge, last week, Beeld said. Angola would guarantee that the estimated 19,000 Cuban soldiers now in that country would not interfere with the electoral process and that they would remain north of a "red line" during the election, Beeld said. The location of the line was not specified.

Other amendments mentioned were:

* Parties involved would agree beforehand to a declaration of human rights to be included in Namibia's future constitution. This bill of rights could be altered only by a two-thirds vote in the future legislature.

* SWAPO would have no bases in Namibia during the election and its bases in neighboring Angola would be monitored by the U.N. force.

* SWAPO would promise that if it won the election it would not allow any group to use the territory as a "springboard for terrorist attacks on South Africa."

* Walvis Bay, Namibia's only deep-water port, would be considered part of South African territory and negotiations about it would be held after independence. South Africa claims Walvis Bay as its own territory since it was administered by Pretoria even before the mandate over Southwest Africa.

The proposal that the U.N. peacekeeping force largely comprise Western troops is the most significant amendment. South Africa and its political allies in Namibia have objected to a U.N. troop presence during the elections because the United Nations has recognized SWAPO as the "sole authentic representative of the Namibian people." A U.N. troop presence, they argue, would be a boost for SWAPO during the election, especially among the mainly black peasants.

To meet this objection, the U.N. peacekeeping force would wear their national uniforms rather than those of the United Nations, according to Beeld.

The presence of the Western forces could, in South African eyes, help dissuade Cuban forces in Angola and the Soviet and East German advisers there from taking advantage of any situation that might arise during the election process.