I drive a 95 V6 Mustang which is identical to yours. and I'm lookiong to do the same thing. I was going to drop in a 5.0 but they told me it would be way too costly because I'd have to change the entire front end to support the new engine and weight. Not only that a lot more has to be changed. Fortunately I have an 8 cylinder transmission in my car (long story) but still it's a big deal. I was thinking of a 351 Cleveland too but I got the same negative replies. For now I go t aflowmaster muffler but I'm going to buy the flowmaster system for 94 - 97 V6 mustang that converts the car to dual exhuast. (
www.flowmastermufflers.com) I've been told by mechanics it'll sound better than a stock 5.0. Aside form that it adds horse power. I'm also going to add intakes and eventually plan on adding a Saleen supercahrger. If you can think of any other or find out of any affordable solutions to our goal please let me know! Good luck