I now have driving time on my Fairmont M/C with manual brakes and disc conversion up front, same M/C as Joe’s, and although it’s a long pedal I find it very acceptable with easy modulation and good stopping. No brace cutting needed, slight movement/grinding of the current relief for the M/C in the unibody frame flange, NBD.
I had to disassemble my front control arm bushings and chip the grease out. I could not get them to take new grease at all. So I would be wary of driving it if on injecting new grease it did not displace what was in there and gush out. Ball joints and other grease areas same issue.
My 62 convert is not in as nice shape but I am keeping it a survivor with no repaint. The interior paint was pretty oxidized (convert) with some bubbles here and there. I used a very fine polishing compound by hand and then paste wax and it came up very nicely. Even used Eastwood clear Rust encapsulator on the rear trim panels for the quarter windows after a 1200 grit sanding to remove some surface rust and it came out OK, not restoration quality but it’s a survivor and looks good. Your coupe should come out nice.