I have an IOR 2X12-32 scope with high rings and yesterday, my ARMS 40L came in and when I went to mount them, the scope would not clear.  I had an extra set of ARMS #17's laying around so I mounted them on my AR and then mounted the scope on top of them and it obviously cleared.  And after checking, I was pleasently surprised on how much more comfortable it is now.  My head is pretty much straight up and down, but I can't obtain a cheek-weld position because the scope is higher.  I guess  you can call it a chin-weld position .  Will this cause any problems with obtaining a repeatable position or any other problems?  My only other option is trying to get a set of medium height rings and it should fit.  What do you guys suggest?