Narrowing IRS the easy way?

[Turbo_Rich]

Hi, just need to bounce some ideas off people. I need to loose about an inch from the back of my bug so the tyres will not foul the arches.

I have IRS and have been looking about an easy(?) way of doing it. I see that if i remove the 1/2" spacer that sits between the bearing and the flange it would give me approx 1/2" inset however, the grooves/splines on the output shaft cease at the point of the spacer. If these were to be extended in 1/2" this would allow the hub to be moved in. Would this generate a weakness in the output shaft. Is it likely to cause any other issues?

On top of this i have thought about machining the back of the hub by 1/2" to give more room, this is giving less material on the hub and would it withstand 200+ bhp!?

The easier alternative is to switch the wheels, but i like the 7x16" Fuchs.

Thoughts would be appreciated