Motor Swap on a 63
At some point, V8 and slant six center links were the same; can't remember what year (thinking 66). Otherwise, everything is pretty much the same except for the firewall. 63 is different than 64-66; as said above, there was no V8 option in 63, and there's a hump in the 63 firewall right where the V8's distributor needs to go. One other thing is that 64-66 V8's had cable throttle, while 63-66 slant sixes had bellcrank. On 64 and later, it's eazy peazy to swap to the V8 setup. Firewall is already dimpled where you need to drill a few holes, then the V8 firewall stuff bolts right in, and you run a V8 pedal. (Of course, all of this is harder to find than it used to be.) But the 63's firewall electrical junction is right in the way of the V8 pedal setup. However, you can trim a later A body (67-76) swing pedal, drill an extra hole or two, bolt it to the firewall and send the cable through the hole where the slant six bellcrank went. And if you want to go a bit further, you can cut off the swing pedal and weld a 64-66 V8 spoon in its place. Then you just bolt the V8 pedal to the floor and you're ready to go. First pic below shows the later A body plate trimmed and bolted to the firewall, with the V8 spoon welded on. V8 floor pedal is pulled back so you can see the firewall setup. This was taken before I replaced the firewall insulation. Second pic shows setup with new insulation and V8 floor pedal in place. Last pic shows what it looks like from up top. Most people will never know it's not factory.
At some point, V8 and slant six center links were the same; can't remember what year (thinking 66). Otherwise, everything is pretty much the same except for the firewall. 63 is different than 64-66; as said above, there was no V8 option in 63, and there's a hump in the 63 firewall right where the V8's distributor needs to go. One other thing is that 64-66 V8's had cable throttle, while 63-66 slant sixes had bellcrank. On 64 and later, it's eazy peazy to swap to the V8 setup. Firewall is already dimpled where you need to drill a few holes, then the V8 firewall stuff bolts right in, and you run a V8 pedal. (Of course, all of this is harder to find than it used to be.) But the 63's firewall electrical junction is right in the way of the V8 pedal setup. However, you can trim a later A body (67-76) swing pedal, drill an extra hole or two, bolt it to the firewall and send the cable through the hole where the slant six bellcrank went. And if you want to go a bit further, you can cut off the swing pedal and weld a 64-66 V8 spoon in its place. Then you just bolt the V8 pedal to the floor and you're ready to go. First pic below shows the later A body plate trimmed and bolted to the firewall, with the V8 spoon welded on. V8 floor pedal is pulled back so you can see the firewall setup. This was taken before I replaced the firewall insulation. Second pic shows setup with new insulation and V8 floor pedal in place. Last pic shows what it looks like from up top. Most people will never know it's not factory.