Stopped trying to polish a turd. Realized that everything in the signal chain had to support the tone I was looking for. I wanted JCM 800/Plexi tones and most of the amps I had were Fender voiced circuits - close but no cigar. 'Polishing' with pedals got me only part way there. Bought a JCM 800.
My current amps are pretty much bone stock handwired tweeds, so short of messing with amps I think are already great, I went and bought proper covers for transporting them from home to jam to gig and back.