I agree w/oops. start low, stretch at home. cutting down saddles in the boat is a pita compared to gluing on a piece. I think the discomfort for a lot of c-boaters really comes from too much or too little ankle padding. That part, for me, has to be perfect. I don't really pad my ankles, I pad from my knee to the ankle..tapering to zero.
But It's all very personal preferences...
And just to add some more confusion.
I don't really subscribe to the "wider saddle is better" theory like a lot of folks. for me (also a cyclist) 6-7 inches wide is more than enough, and more width just gets in the way of your feet.
Buy twice as much foam as you think you need, and get
weldwood in the RED can.
