Used the thin cutting blade wheel for the dremmel tool as tim described, cut until you get through one side of the snap ring, then push with small screwdriver until you get a gap on the other side, then pop off. I just did all but two windows all yesterday as I ran out of gasket material. Also used a chissle to scrap out old gasket and then a wire wheel and drill to remove all old gasket and glue. Super easy this way. Thanks also to Tim for his help.
next is the bathroom. Yee Haw!