I‘ve done lots of plastics on 350‘s and 400‘s using Sump Magnets method - definitely do not use paint stripper - even the environmentally safe crap they sell these days will ruin them. I start with freecut 150 on a soft foam block to get the bulk off, then a short piece rolled up to get into the awkward grooves and corners. Originals were a cream coloured plastic, so you know when it’s all gone. Then repeat the process with freecut 320 and after panel wiping, you are good to go with plastic primer, high build and colour plus lacquer, flatting with 600 in between. Good prep and patience is the key.
Ian