There is a thread I did here about removing the steering wheel if it helps :
http://www.madabout-kitcars.com/foru...ead.php?t=4917
I then had a mate machine up two round pieces of aluminium. One bolted to the steering boss the wheel was fitted to that and the other went on top to clamp it into place. That was only necessary because the centre of the wheel didn't fit the BMW steering boss.