Yes, its a popular swap. You have 3 options in terms of the MAF:
- Euro M3 (3.5 " MAF)
- e39 540 MAF (same as above)
- Dinan (same as above but more $$)
You can get your TB bored out as well... it will improve your throttle response. Contact Randy (Empowered) on this board as he can do this for you. He'll be doing 6 for me soon

Dinan also has a bored out TB on an exchange basis but its more expensive plus Randy can go bigger
However, before you do this, I would strongly suggest that you do Schrick cams first then after thats done an M50 manifold with 24lbs injectors, the MAF/TB and software. If you do it in that order you'll have the biggest gain per $ spent.
T.