Rich,
You said the same thing in another post.
I wish that you were right but by looking closely at the sill,frame and insulation,I don't see how your idea will solve this problem.
Yellowing always happen on the top of the sill because hot air will always go up.
The insulation in the sill is shaped like a U and the one on the frame like a I.
Both of my sills insulation are damaged/burnred because,as you said in the other post,they rub/make contact with the cat.
Problem is that the insulation on the frame side ALSO is in contact with the cat.
So if you "push" the cat toward the frame, what do you get?
You will still have contact between the cat and insulation,and the heat will still have no way to escape and will still rise to the top of the sill.
It is inded a design flaw.
Why don't ALL Vipers have this problem?
Honestly I don't know what is the % of cars with or without this problem, but there is some reasons why.
Depending on the paint color,some are more "heat resistant" than others.
Not all engines put the same amount of heat in the cats.
That can be due to many reasons:
Driver style
Engine tune (ignition advance/retard,fuel curve,lean/rich,etc)
Quality of fuel
Exhaust back pressure,the more back pressure the more heat,that can be due to the variations in manufacturing tolerances.
The cats,due to the sames manufacturing tolerances
And finally the outside temperature.
Luc.00GTS
