I'm thinking a small garden tractor with a manual transmission, anything with pullies and friction clutches is just going to burn up....or maybe one of those little "tote" tractors they use at airports to pull around small planes and boats at marinas.... :idea:
http://p.airliners.net/photos/photos/9/7/6/0879679.jpg
Or maybe a jeep or samarai....j/d :cry:
:rollside:
Not trying to be a d!ck but what about the liability issue if something went wrong and someone else got hurt. Insurance would probably laugh when they found out what you were pulling the boat with. It sounds like you have alot to lose, might be something to think about.