Steve I understand what you did,,,
My 1933 Vicky has a kirkey Seat that we modified, streghthend and added the ISP Stealth Head and Shoulder Supports to,,, so my $200 Seat ended up at just under $600..
For the Stude, I just decided to go Full Containment from the get go and have a Custom made ISP seat... custom built to me (and using double thick sides and back plates for my weight)..
Charles