Heck, you'd be money and time ahead to just get a rebuilt from a parts store, they usually come with a good warranty and would be the quickest way to do it. Couple of the parts stores here sell them for around $1,000.00 exchange with a 1 year warranty. Most of the junkyard stuff is going to be old with a bunch of miles....Ford started putting the Modular 4.6's in about '92...The Mustang's had the 302 for a few years longer but then you're into an engine that's probably had a tough life already!!!!