With that number of coats on the hull you might want to try a heat gun and a dull putty knife first and then finish off with stripper. Have used this method pulling off epoxy coatings- but don't go nuts with the gun until you see how much it takes to soften up the varnish.
Hadn't thought of that. Thanks! I have learned my lesson with too sharp of a scraper, having to epoxy a bit of the veneer sheet back on the ply. Good thing I am going to paint when I am done. (I want to lay thin glass on the hull, as I am getting a little checking)