Well, I am going to check with the huge "central shops" that services our police cars. I know they have some stuff for Explorer police versions, etc. and maybe there is a leftover from a crashed car that will fit. If that doesn't pan out, there is a Flowmaster dealer in my town, and I'm going to ask about the 50 series, mounted as far back as possible. I will leave the cat and resonator in (probably) initially.
The local muffler shop wants $215.00 for an installed Flowmaster 50SUV. He checked, it will fit and he said it would be decently quiet inside the cab. If I can't get something from the police garage out of an Explorer, I may go this route.