The ratio that we are talking about here is 4.10. They were available in some 3/4 Ton trucks from 67 to 72, with the front loading "pumpkin". I did this to my truck and I can cruise at 60 mph but I usually don't push it over 55.

1951 GMC 1 Ton Flatbed -- It is finally on the road and what a great time I have driving it!
1951 1 Ton Completed

My Chevy Master 4 Door is on the Road!