A 5.17 ratio was an option in 3/4-ton trucks and standard in 1-ton trucks. You are not clear which direction you are trying to go...
If you need something more highway friendly than 4.11 you probably need to swap rears. I've been told there is a 3.something out there, but no one ever seems to be able to find one.
I'm not sure what else would fit, but if you take a tape measure to the wrecking yard you should be able to find something close to the right width.
