I too have a 37 GMC, it is a T16 and it has the bumper with the dip in it. I assume it to be original. I bought the truck from the original owners grandson when I was 14 almost 30 years ago. Mine had a 216 in it when I got it. It has been off the road for too long, hope to get back to it soon.
Jason
1937 GMC T16 468 BBC th350, 4.10 1941 Dodge COE 5.9 cummins, 9 speed roadranger 1947 Diamond T COE, hercules and 4 spd, all original 1955 Chevy LCF 9.0L IH diesel AT545 1962 Corvair (Elsie) 1967 Jeepster Commando 1968 K10 1970 Chevy C50 box truck |