Allow me to start with the fact that I do not own a Mustang. I do however have some take off parts I am thinking of using on my '40 Chrysler.
I am thinking of using a pair of mufflers off my cousins '13 (v8/manual), but not sure how well they would do with my big block. They were taken off at ~5k and are in great shape, so I am not worries about current condition. My question is, how well would these mufflers handle the flow of a big block? Or should I just sell them and buy a set of Coffin Mufflers? When I rebuild my front end, I am going to check on using the springs off the mustang also, if they aren't close, I'll sell them.