Li Shang-tao has returned to his comfortable office job at Peking's No. 2 steel rolling plant, after eight years of pitching manure in his native village because of a few indiscreet remarks.

Li was stripped of his job and Communist Party membership in 1970 for expressing impatience with the ritual recitation of Mao Tse-tung quotes each morning and evening in front of the chairman's portrait.

The practice, since discontinued at the plant, is now blamed on overzealous Mao supporters. Li, along with perhaps hundreds of thousands of other former office workers, has been exonereated for past deeds and restored to work, bringing the new post-Mao leadership a needed dose of popularity among intellectuals, scientists and skilled workers.

But the New China News Agency story of Li's return to the steel plant gives no hint of anyone being fired to make room for him. In fact, Peking is now showing signs that its massive political rehabilitation program, no matter how popular it is, has created a bureaucratic glut that could imperil plans to revive the national economy.

The officials winning back their old jobs include untold thousands who were persecuted and forced to retire by the now disagraced Gang of Four led by Mao's wife, Chiang Ching. She apparently considered such officials too untrustworthy, too uncooperative or just too old. Another estimated 100,000 persons who were purged in 1957 for supporting "rightist" criticism of Mao's policies have also been officially rehabilitated.

In many cases they have been released from work camps to return to office jobs, according to Communist sources here and in Peking.

Since the mass rehabilitations began, Peking has sharply curtailed its hitherto regular calls for "simplifying administration," that is, cutting office staffs and firing unproductive personnel. Such office housecleanings apparently force too many difficult decisions, such as whether to squeeze out the thousands of recently rehabilitated men who have just returned to work or fire the often younger men who have been filling their jobs well enough.

The government clearly is worried about the problem at a time when it needs popular support from both old and new office workers and must also increase bureaucratic efficiency to carry out rapid modernization of the government-run economy. At a little publicized second plenary session recently, the standing committee of the Fifth National People's Congress - China's parliament - gave tentative approval to an apparent effort to coax older office workers into retirement.

Most Chinese bureaucrats appear to shudder at the thought of leaving their jobs. The ideal death has been to keel over at one's desk. Office positions carry steady salary and rations, and occasionally perquisites like access to a car or special theater tickets. In socialist China there are few family homesteads to retire to, no stock coupons to clip and few comfortable retirement communities.

Li Shang-tao was forced to go back to his home town and, as the official news agency says, "do physical labor under the surveillance of the masses." But even if he has retired and returned home voluntarily, life would have been far harder than he was used to.

At best, elderly retired workers and peasants are expected to busy themselves looking after their grandchildren or helping in the fields at crucial times. So bureaucrats have generally tried, and have been allowed, to stay at their desks as long as they are alert - and sometimes longer.

The Congress standing committee, many of whose members are themselves in their 70s and 80s, approved in principle two measures for handling officials "who are old, weak, ill or disabled" and "for workers' retirement and cessation of service."

The official news agency account of the session gave no details on how retirement conditions would be improved. But it quoted state labor bureau director Kang Yun-ho as saying, "such arrangements . . . are of great importance for maintaining fewer but better forces and simpler administration [land] speeding the growth of the national economy. . ."

With several veteran officials and former purge victims like Vice Premier Teng Hsiao-ping running the government, the accent for now remains on returning rehabilitated office workers to their jobs. There are regular complaints in the press about offices dragging their feet in bringing old officials back into the fold.

For many, nothing can be done to repair the earlier damage. A Hong Kong resident who recently travelled to Canton and met some friends purged in the 1957 "anti-rightist" campaign said, "They are in their 50s but look like they are in their 60s owing to what they have suffered in the past 20 years."

A radio broadcast from Canton said seven elderly officials purged 10 years ago had finally had their "reputations restored." But all that could be done for them was to transfer their remains to a better cemetery.