I just bought my second Cougar, a 1967 XR-7 GT "S-code" after 18 years of waiting. My delema is should I keep it the factory color or will it de-value the car by changing the color? The engine numbers allready don't match, it has a 66 block and 58 edsel heads along with a 63 dual quad manifold. I will be using this engine in the car. The body is absolutely perfect, not rusty at all and not cut up. Just want to get some advise on peoples thoughts when it comes to GT's and big block cars.