I looked it up in the Stant OnLine catalog , Stant P/N 10623 , NAPA BALKAMP # 703-1220 . Some older GM #'s too : General Motors 10053486 General Motors 228498 General Motors 322781 General Motors 3845429 General Motors 3914958 General Motors 6272317 General Motors 6410233 In case you're a Flea-Bay maven . This fuel filler cap fits all GM Trucks 1937 ~ 1970 and most Passenger Cars in that period too . I hope this helps .
