John at All 4Wheel Drive does good work. I've always used Diff Works in Corona on my personal vehicles though and in fact in my former career we used to send all out gear work out to them so I've sent about a hundred or so jobs there - all axle types. Not one come-back. It's what they do!
They've even been on Overhaulin several times.
Ask for the owner Steve. 951-549-6780 He's a great guy.
Big Red:'93 YJ, SOA, Deaver leafs, Fox shocks, Dana 44 front w Reid Racing knuckles, Ballistic Fab high steer, Detroit, Superior shafts & Warn hubs, Ford 8.8 (31spl/discs), "Super 88" kit, Detroit, Dana 300 w Low Max 4:1, 35" BFGs, Allied beadlocks, Mastercraft seats, Currie bumpers, Warn sliders, Gen Right fenders