How much Mohs to cover a 20 foot boat?

Looking to do my 20 foot fiberglass boat:

http://i1253.photobucket.com/albums/...pskexhiilv.jpg


and cover it with 2 coats of Moh's at least (maybe the full Syncro treatment?) but I'm worried if 50ml will be enough as there is a lot of fiberglass to hit. Thoughts?

I know this is a month old but for reference, I got 3 good coats on a Ram 1500 with a 50ml bottle. I just barely squeezed out the 3rd coat with a tiny bit left in the bottle.