IME, if the paint *is* that soft, the #83 and #80 will have too much initial bite and will leave micro marring. The only thing that I have found to work after compounding paint that soft is 3M PI-III MG, OP, or FP-II.
I would try (insert compound of your choice, I would probably use HT-EC or #85) with a twisted wool pad @1500-2000 RPM's.
Then step to the 3M or OP with a polishing pad @1000-1500 RPM's
Then OP with a finishing pad @1000 RPM's
At that point *I* would have to then make a pass with the PC (I am not that good with the rotary) and I typically use OP or the 3M PII-III MG.
Follow up with 1Z MP, and LSP.
At least that's what I would try.
The afters look awesome!! Perhaps you have found the right combo.
