I'd say it's aftermarket but that's not to say it's not 'correct' for the truck. A large percentage of trucks in that era had aftermarket heaters. I imagine they were a lot cheaper than a dealer installed one.


"It's just a phase. He'll grow out of it." Mama, 1964

1956 Chevy 1/2-ton 3100
1953 Chevy 6100 "The Yard dog"
1954 GMC Suburban Now with a new proud owner.