Dart Gas Pedal Assemble

i have a later model gas pedal assy. with a cable and everything that a buddy gave me. looks just like the one in my 75 scamp and my dads 72 dart. but it doesnt fit the firewall on my 63 very well. im sure i could get it to work. but i saw the aftermarket setup on 64dartwagon's car and i like it. so that is the route i am going to go with. i was originally trying to find a 64-66 v8 gas pedal but they are hard to find.