Crawdad Gilmore, a 93-year-old presidential adviser, is murdered by a couple of muggers before he can reveal what he's overheard in the men's ""crapper' of his private club. All we know is ""something hot"" will take place on July 11. . . and it's up to two of the old man's friends to find out what. They're Ancel Easter, the successor to Gilmore's law firm, and Jake Pope, a multimillionaire former Senate subcommittee investigator. The hanky-panky involves a GS-14 who has access to the Department of Agriculture's official wheat crop estimate. The forecast will enable a sadistic young tycoon, Fulvio Varvesi, to use syndicate money to make a killing in the commodity market. That's a money harvest--not that you're likely to be all that bullish this time.