I tried to remove some lettering on the side of my boat today with easy off oven cleaner (suggestion of a friend) and it removed most of the "one shot" paint but left the name legible and discolored the gel coat from white to off-white. Should I try it again? Use paint remover? Try sanding and bufffing? Any suggestions?

I would try wet sanding and buffing. Its good you got the paint off. Now I would wet sand with a sanding block starting with 800 grit then going with finer grits until around 1500. You may need to start with a courser grit. But alway use the finest grit needed for the job. Then of course followed by buffing. The key is to use a nice straight hard block. I have seen guys take off lettering hand sanding the area, paint it and the letting still shows at certain angles. I would not put any more chemicals on it at this point.

zactly what Russ said . . .

stick with a hard block and let the block do the cutting dont use a lot of pressure. May hafta to drop down to 600 or so for a light leveling pass but not much, let the block ride over everything. good luck.