I've got a 25th Anniversary Edition Hollander Interchange Manual (covers years 1949-58 for most cars and trucks) and it's limited on interchangeable stuff for GMCs from my random reading sessions through it.

You can purchase a reprinted 1939-54 GMC Master Parts Book that will provide you a great baseline of original part numbers, if you don't have something like that already.

There is a pretty good GM Parts searchable database at GM Parts Wiki that is I use a lot to help search for and ID part info. Not the be all end all, but a good tool to help track down part numbers, replacement numbers and/or parts used on multiple brands (GMC/Chevy).

You can also ask for specific help here in Stovebolt any time. There are several members (myself included) that have "Stovebolt Libraries" which folks are willing to search and share info from. Just be sure to ask about specific items in the appropriate tech forum to help get you the best help and answers possible. wink

~ Dan
1951 Chevy 3 window 3100
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"My Grandpa Carl's Truck and How it Became Mine"
1966 Chevelle (Wife's Hot Rod) | 2013 Chevy Silverado (Current daily driver)
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