Firstpft
actually I was asking same question a few months ago as wanted to take some paint stenciing a stickers off hull
I read some where that Oven cleaner was the go
Originally thought this was a joke
However the stuff came off
As I was in process of having to remove the paint and stenciling from the other side of boat, thought I would post a few pictures of how the ease off oven cleaner worked
this was removing paint from Gelcoat
Ist pass
sprayed on ease off, left for 25-30min
used putty knife/scraper, not sharp (non-razor blade), took the majority off after 10min cleaning
2nd pass
sprayed on ease off, left for another 25min
used putty knife to clean up remaining paint, and then handy towels to clean side of boat
needs going over with acetone and 1200 grit wet/dry, however majority of paint now off,
the sanding/polishing will take care of the shadow effect that is left, followed by polish
hope this helps