How to build it?

[RC-Monster Mike]

The bearing holes have a very tight tolerance. The UE VBS is about the same, to be honest. Most every intricate design will have slight areas where you may have to trim a touch (UE VBS is tight in the suspension arm area, for instance). I wouldn't dremel th bearing holes, though. The bearings are snug, but they will go in. Also, one diff setup kit is usually plenty for a pair of diffs. You may not even need those, but better safe than sorry.