I have an aftermarket Power ASC Sunroof on my 73 Mach I. This is one of the reasons I bought it, besides the 21 or so options including Q code 4sp power windows, AC etc. and originally sold and lived in Beverly Hills Ca.. Keep the sunroof as it is a better story than a replaced roof and makes your car more unique. Some cars are better restored to an era in their history than factory. If people complain about it, it is about them more than your car. Plenty of non sunroof Q Mach's to go around. Be unique. Be confident your car is better than those dark inside cars. Your car will be more original with most of your original roof still intact. Don't erase that. In College had a 71 Boss with a sunroof like yours and loved it and I currently have two Mark 1V's with ASC sunroof's and an ASC McLaren. Some of us like quality changes like ASC did. As far as I know all "Factory" sunroof cars were sent to ASC for conversion so not really "factory". Yours looks like an ASC Sunroof, just added sometime after the Marti report unlike "factory" cars which were on the Marti. You have the best of both worlds since they didn't make a Mach 1 convertible.