A quick update.
It is still too lousy to get the pickup in to the shop, but I looked through the supporting material I have for this truck.
The truck was bought in Coaldale, Alberta in 2008. The key-chain has a 1976 War Amps of Canada Tag # 118939 and a coal=miners tag like a star with ‘40’ stamped. (picture)
Contacted War Amps, waiting for reply. Found tag in the truck from Enerson Motors Ltd. Pontiac – Buick – GMC Lethbridge, Alta. Lic. No GMC 1 TON Handwritten: E. Anderson, Barnwell
No papers in the clove box, but lots of mouse nests (juck)
