My current GB has 2 gears with stuffed synchros and I also plan to install a 3rd party helical LSD and a 4.7 final drive.

I would like to do this as cost effective as possible, but not if it means a big risk in reliablility.

Would you recommend rebuilding the current box, or purchasing an ITR box with similar OEM specs?

I am leaning towards the ITR box purely for simiplicity...