joninjax,

Check then engine serial number on the pad to the left of the distributor. GMC encoded the engine size in the first few digits of the serial number. i.e. 248..., 302...


'38 Chevy 1-1/2 ton
'49 Chevy 1/2 ton
'54 Chevy 6400 2 ton
'55.2 GMC 3/4 ton
'56 GMC 1-ton

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