Originally posted by fordsfairlane
I agree, and that if a buyer would happen to notic the heads had been changed, he could walk away.

if the car is a numbers matching car then leave it alone . but that doesnt mean you cant do a good rebuild, just dont swap heads intake and such, you can open the cylinders a little to like .020 over, add new rings and bearings, maybe new cam, and get some work done on the original heads, like 3 angle valve job, maybe new valves ,guides and seals.
you would bring the hp up a little and still have a numbers matching car.
.020 over cylinders?