Help!!!!

I was rushing to put the final fill coat on the hull as we were leaving for 3 days of vacation. I figured it would well hardened by the time I returned. I now realized I goofed on the hardener to resin mix and now I have a sticky mess. It got up to 93 degrees on Wed and shining a lamp on it still haven't helped the cure so I am now faced with getting this mess off the hull.

How can I get the un-hardened epoxy off? Every 6 months someone answers this question but I never paid attention because I thought I would never make a mixing mistake.

Scraping seems to just spread it around. Sanding just gumms up the paper. I know there a solvent that will remove the gunk but I can't rememer what it is. Yuck!!! Next time I will never do epoxy when I am in a hurry.