What is the diameter of your pivot pin and locking pin? Are they both exactly the same?
IIRC, if they are both .248", you are in good shape. Other than some oddball Colt lowers and uppers, virtually all others use that size. There are even adaptors made for the Colt non-spec comonents so as to allow mating to standard-size components. But that's something of a PITA.