You don't need an adapter to bolt the engine into your truck using your transmission and bell housing. You may need to drill holes in the lip of the front mount plate. You will need to shorten the '58-62 water pump or use an adapter and your old water pump.

"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.