Curtis,

Any hints to get us started?

GMC?
Approximate/guess of the year?

If it is a GMC: 101 = 1/2 ton GMC with a 116" wheelbase
100 = 1/2 ton
1 at the end of 101 = 116" wheelbase

Rob English's oldGMCtrucks.com personal website has decoding information for many years of early GMCs but I cannot get that site to respond. I'll keep trying.