Getting the foam
There is a retail outlet near Asheville, NC called Foam and Fabric Outlet that sells all sorts of foam and upholstery materials. They had 2ft. x 2ft. blocks of the memory foam for about $12 a block. The blocks are two inches in thickness. The stuff is surprisingly heavy - I didn't expect that.
I hadn't planned on doing the rear part of the seat, but having seen how easy it was to do the front, I think that I will do it too.
Edit, May 25: I went back and added some stitching to the velcro today. It hadn't slipped, but I got to thinking about the coming hot weather and the possibility that the hook and loop might start moving when it gets hot. I just popped the cover back off and used a needle and some heavy duty polyester thread to secure the velcro to the seat fabric. That should hold it even when the temps start getting unbearable. As far as the ability of the hook and loop itself holding, I think that it will be OK. That is some seriously strong stuff.
Last edited by VeeWNC; 05-25-2009 at 05:06 PM.