Hi Michael

I believe that if your chambers was the old TYGA versions that they were specific for MC28 you wouldnt have these fitting problems.
Many owners care for the performance of their NSRs and try to find every single hidden pony as these bikes are for hobby,fun and racing.
Recently i bought with my father who is an old street bikes rider a GSXR 1000 K9 and i have to say the fun and excitment that NSRs bring me when i ride them,simply GSXR dont have it !!!Although it has 3 times the power of the NSRs.
More power on NSR is more exciting.
I love NSRs for their weight,geometry and of course the 2T engine and sound.
This is my opinion and hope that someone else will reply for your chamber problems with some info on how to recognize if they are old MC28 specific type and any experiences of their fitment as the discussion goes a little out of subject.

Thanks
Stefanos