B4 vs B4.1 diff and bearings

[grelland]

Hello there.

I have just ordered a vega conversion kit for B4, but I have a question.

My car is a B4, not B4.1, but as I understand the gearbox for the vega is designed for the B4.1. What is actually the difference?

I understand the B4.1 uses metric bearings, but is it enough just to swap the bearings, or do I need a new diff also? I looked at the listings at losipartshouse, and from what I can see, the outdrives have the same part no for both the B4 and B4.1...

Anybody out there that can shed some light on this for me?