yeah the normal GT40 heads will work, but the P heads have a different spark plug angle which wont work unless you use the MAC "P" headers or the motorsport shorties

Ya. they're hard to find but they're definatly out there. there's a crap load of junk yards around me in newark and jersy city. ill keep an eye out for you for the gt40s. he got his from a junk yard in kearny called Bibs. He got them for 150 bucks.