Due to Ford's production variances, as well as the ability to mount the MM phb a little fore or aft of where it ought to be, it's pretty hard to predict.
My stock pipes had to be massaged a bit to clear the phb, but since the h-pipe needed to be modified anyway to clear the t/a mount, it was no big deal. I's suggest just putting the parts on and, if you have a problem that can't be fixed with minor grinding, get thee to a good muffler shop. They should be able to fix it for $50.00 - $100.00.
Mustang - The Great American Kit Car
#50 ESP/SM2 (backup) - Cal Club
Porsche - The Great German Kit Car - #50 SM2 Cal Club - #84 JP PCA