I tore my factory transmission down to the driven chains something like 6 times, put a new 4th shaft\clutches in, new TCS, PCS, and a new VB\CP with Sonnax upgrades and such. Then I ended up picking up a JY transmission from a Century (IIRC) and used parts from both transmissions to make one good one. Century transmission had plenty of life left in it, but I used a steel for the second stack of my factory transmission in it, stuff like that. Also picked up some GXP chains, and used the N\A torque converter since it was a LOT lower mileage and higher stall. I'm not 100% satisfied with the new transmission, but at this point I think it's the VB\Channel plate. I kept the one from the Century so I'm going to go through it and swap over what I can from this one. I might even just use the extra separator plate I have instead, since this one is drilled, and I think that might be it.
http://s14.photobucket.com/user/boob...00%20GTP/4t65e