The upper limit for the 9.25 is about 38s, and you'll need to regear both axles. If you dig into the pumpkins, might as well add a limited slip or locker particulary in the rear. $400 is simply too much for a Dana 60. You can find rear axles in junk yards with 4:10s usually less than $100. Front axles are alot more expensive. You can keep it and fix it up, but you should make some changes. If you can't get a front Dana 60, at least go with a regular hub, Dana 44hd (8 lug axle) or swap the outers to 8 lug hubs. You won't gain any additional strength over what you got now, but you'll have better and bigger brakes for those big tires, and you won't need to carry two spares (One 5, one 8 lug)
Ed
Ed