I have a '67 2dr coupe, as well as 2 '65's, I prefer the looks of the '65's, but they have the narrow engine compartment, header fit is a royal PITA, and anything wider than a 351w, you really need to notch the towers. The '66 up body style is really a lighter, short wheelbase Fairlane, even Fairlane 2 door sedan glass fits the falcon. I am putting a 351C/aod combo in my '67.
I agree with falcon67 on the value, my car is a second owner, ( my grandmother bought it new from West Coast Ford in Maple Ridge) 32,000 mile car, I tried to sell it a couple years back, I was asking around 5k, would have sold it for 4k, guys were offering $1500. I have 8 cars, but I thought "if that's all I can get for it, screw it, I'll put my Cleveland in it and keep it!"