What engine

I got a 65 Fastback with a 289 bored and stroked .030 over, hooker headers, Flowmaster 2 chamber exhaust, you name its got it straight from the 70s. Im thinking of either changing to a 351W and keep it an auto with plans for a bore and stroke so that it becomes a 427, should I do that or should I keep it the way it is and change it to a six speed tranny?

It depends. Do you want to keep it original with the 289? Or do you want to have one hell of a fast car. Do you show your car more or go to the track more with it? I had a 65 fastback 289/4spd. toploader. It was stock except for Edelbrock 650 and Performer RPM intake. It was OK as far as hp but, my 5.0's were alot faster stock. So I sold the car 2 years ago and plan on getting another 5.0 next year. If it had a 5.0 or a 351 bored/stroked, I probably would have kept the car. Hope you have sub-frame connectors!!

Fitting a windsor in the 64-66 cars is no easy task. The best thing to do is cut the shock towers out and install an aftermarket Mustang II IFS. I had a '66 coupe I was gonna stick my windsor in. I ended up selling the car and buying the current car in sig.