I changed my 4.27 original axle to 3.50 by swapping in a 9" from a 63-65 F100.
I think it's about optimum - my 48 was my daily driver for 10 years and logged trips from Washing state to Ohio, and Canada to Colorado. Mountains or plains, the 3.50 handled it all with ease.
I'd say you got lucky and have the tough part already in place!
Like Ray said, the only improvement I'd make is to add an OD trans (T5) or swap gear sets to get 3.25, but you can certainly live with 3.5 - my road speed is comfortable at 62-65 with 16" tires/wheels
old ray you got a 460 C6? how is that working for you?
No, it’s not a crate motor; actually it is the exact opposite. I horse traded for the car that it came out of many years ago (drove it home) and upon further checking I saw that it had a rebuilders tag on it so I took a chance (crap shoot) .....I just changed the timing chain and installed the engine. Time will tell!
The 429 / 460 is a very heavy and big engine and hard to move around, if you are just looking for a nice running easy to work on engine, I would get a 302 / C4, can’t go wrong.
what engine and tranny you have?
OK. STill need help here guys. Passenger side axle will not come out. What am I missing here. I have tried slied hammer idea, heated the axle, sprayed it with every thing I can think of to get it out. the axle still turns but no longer turns the ring gear.