02 audi a6 3.0. camshaft control valve issue
 

Hi.
I'm having an issue getting the camshaft control valve back on to engine on 2002 a6 3.0. its a Quattro, but that probably makes no difference.
The issue is getting it to butt up to motor. It seems like it's getting caught on the piston rings at end of cam.
The other side went on fine. This side I did once already and when all put back together, it leaked oil like crazy. Took it apart, got a different control body, since the other on had signs of scraping, now back to same issue where it wont slide on nice.
Any suggestions? Or is there a trick to it?
Thanks
Fishman