Any suggestions on how to remove waterproofing

`Roger
The maker of the waterproofing should be able to supply you with a material
safety data sheet , this will list the main ingerdients in it. The makers of
the viynlester resin should be able to tell you what effect these chemicals
may have on a finished layup.Most cured layups are pretty resistant to mild
solvents and detergents.Search the net for info on the chemicals in the
waterproofing, and also for info on the resin.
Regards
Ken Reynolds