I have seen one pic of a car with an approx. 1/4" aluminum edge on the body opening for the sidepipe. This trim actually wrapped around from the inside and layed flat on the body. Can't find the pic to ask the author how this was done. If anyone knows what I am talking about and how this can be done on a fiberglass SPF it would be greatly appreciated!
The reason is that I have developed several small paint blisters near the back edge of the opening. Timing has been checked and is at 12 degrees BTC for this 427 at idle. Headers are standard SPF, jet coated and perfectly aligned in the openings. Cooling air was used during the initial start-up on an already hot tested motor. Go figure...?