Not all of the black paint could be stripped off which is good. I've been using it as a "guide coat," an indicator showing areas that have been sanded thoroughly when gone.
I've been outside sanding when time allows and the job has been going by quickly. So far I'm about three hours into it and 1/3 of the hull is finished.
They tell me sanding is suppose to be done with 80 grit sand paper but it took too long so I switched between that and 60 grit in some places.
The two pix below show the hull as I was stripping off the black paint in April and how it looks after sanding.
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Above is the topside bow. This aluminum was used as a frame for the vinyl. The vinyl was applied with adhesive. Years of moisture underneath the material has caused a lot of damage to the gel coat. Significant cracking all over. I've got a lot of sanding ahead of me. LOL.