Just after adding my post I stumbled over a web site explaining rear mounted systems. I had never seen this before. I think you are right, it does seem to be the way to go. I can't see any disadvantage at all. I can't see why people would suggest lag. The compressed air from the turbo moves pretty darn fast. Same with engine exhausts.

Besides method, does anybody know if forced induction has been done in the M120 V12 engine? Or perhaps some input I could find usefull. My main concern is the compression ratio of the engine and overall engine reliability. If I do go ahead with this projekt I will be consulting Roman "Pumpish" for a megasquirt install. I live in Stockholm and his shop is close by.

Turbo E320: That's a pretty sweet car in that vid. Nice job.