People at the top of the civil service grade pyramid, who now get $63,800, would be earning $106,542 on the outside, according to a recent federal pay study that has civil servants and private industry workers equally furious--for very different reasons.

That draft report prepared for the president by his pay advisers and based on a Labor Department study says that the government is underpaying its own anywhere from 17 to 36 percent when compared with industry.

The president's pay agents--the secretary of labor and the directors of the Office of Personnel Management and the Office of Management and Budget--did everything but hold their noses and snicker when they signed off on the report, which they think is about as accurate as preColumbian maps of downtown Omaha.

Reports on the pay report, here and elsewhere, have infuriated feds and nonfeds alike, according to calls and letters to yours truly.

Government employes say the pay averages Uncle Sam uses to compare them with private industry are too high and make them look overpaid even though the data suggests they are due big raises. Even so, it is a government study, it is mandated by law, so why not follow it and give the raises that are deserved, many feds say.

Nonfederal people who have called and written (and they are in the majority) almost foam at the mouth when they hear that the average federal worker here (earning about $28,000) is underpaid. Compared to what? they say.

According to the government pay report, government messengers, computer operators, personnel clerks, engineers and executives are grossly underpaid--anywhere from $2,000 to $40,000 a year--compared to the going rates in private industry.

Critics of the pay-measuring system say that government employes who made the survey looked at too many big, high-paying companies in the private sector and ignored outfits that employ the majority of Americans, not to mention the 12 million people in state and local government.

They say that the value of federal fringe benefits--retirement, holidays and tenure--should be counted when making value matchups with the private sector.

U.S. workers argue that the survey is fair, that Congress has approved it. They ask if NASA scientists should be compared with operators of Mom and Pop outfits. After all, they point out, the federal government is bigger than any corporation, has more scientists than secretaries and can hardly be considered a minor-league employer.

The salary survey says that employes in Grade 5 in the government are 19.51 percent behind industry; that Grade 7 is 18.08 percent behind; that Grade 11 is 18.88 percent behind; and Grade 13 is 24.69 percent below the industry rate for the same level of responsibility. At the upper reaches of the civil service the pay spread, according to the survey, is even even bigger in favor of industry.

President Reagan won't spend much time on the report, especially since the agents that presented it to him disavow its results. He will try to delay the regular October pay raise until April of next year, but will go along with a January 1984 increase if Congress pushes.

The survey will be used by both sides to prove a point. Backers of a federal pay raise will say the data was collected by the government, and the results are there in black-and-white.

Opponents of a big federal pay raise will say that any report showing U.S. workers 21.5 percent behind industry can't be taken too seriously.

The only thing the pay survey seems to be good for is making everybody angry.