I don't know the answer to that particular question, but what do your plugs look like? Are they wet? Black? Light brown? Light brown and dry would indicate that the mixture was close. Black or wet would indicate too much fuel going into the engine.

The second question would be is this a 1/2 ton? I have a 1 ton and it had 5.26 gears so it would barely go 45 mph.

\'59 Chevy 1-ton
'72 c-10 (in progress)
The Great Rust(less) Mountain
\'47 Jeep cj2a