I just got off the phone with Mark as well, he asked me to try using the stock tubes for the IC to see if they would fit better. I'm going to do that tonight and if the fitment still sub-par to my standards, I'm going to call him back. Mark says that 50% of the time, he has complaints about ill fitting rear tubes on their IC. Time to get this resolved! I think it is as simple as re-welding the inlet on the IC at a slightly more downward angle.
Coyfish, I don't remember you having any issues, do you have pictures of your rear boost tube?