I have a 1998 mustang V6 I've had since I was a teen, and I've been thinking of doing a motor swap.
I got ahold of a 2009 Ford Crown Victoria P71 complete and running, now the question is if anybody has done a P71 swap for an Sn95 V6, and if so what would I be looking for to be able to complete the swap?

 

 

The swap itself would be identical as if the engine had come out of another Mustang. What you are about to do though is a **** ton of work and you are going to need a lot more than just an engine and transmission. The few people I've spoken with who have actually done this swap recommend that you have a complete donor car to scavenge the things you need.

Things such as complete engine wiring harness, fuel system stuff, pcm/cluster/steering column, 8.8" rearend, the list goes on and on. Do your homework, this is a huge project. Very few nuts and/or bolts will go left untouched. It can and has been done, but for what's involved most would say you are much better off to sell your car and go buy a GT. As an alternative to that, since you have (hopefully) a good running engine, I would be on the hunt for a '96 - '04 GT in decent shape but with a blown engine. Should be pretty cheap that way, and swapping that P71 in will be cake.