Very interesting results and issues that developed, but I will have to wait till next week to elaborate.
However, it is safe to say that I would urge those with headers and cats to double check the heat coming from the cats, and to hold off on putting cats on your car. I will say that the heat is enough to melt components

Long story short: my installer did the tape and the tunnel plate AND I am now running without cats. More to come next week.