Your better bet would be to find a 14 bolt rear end with a limited slip center section. Those are EASY to find in the 4.10 gear ratio. You may need to get it narrowed, which a hot rod shop can usually point you in the direction. Its a shame you aren't closer to me as I have a friend who narrows axles and does a very good job for very cheap. Moser can respline shortened axle shafts for about $75 each.
Another option though to running the 30 spline 14 bolt detroit is to simply have a set of custom shafts made of the proper length. There are plenty of aftermarket companies that cut 14 bolt shafts for aftermarket applications.
Here is a link to some 14 bolt information. A Cab and Chasis DRW housing could be used at 63" WMS and will yield you a narrower axle closer to that of the current Eaton.
http://www.pirate4x4.com/tech/billavista/14b_bible/index.html
