Dave-
Early '35s didn't have any bracing under the handle. Late '35s had a additional cross brace put on the lower seat frame which minimized the sagging where the adjuster handle is. I have an early '35 and what I have done is put a thick chunk of rubber under the center section of the seat frame to prevent the center sagging. Enclosed are a couple of pictures showing an early'35 and a late '35 seat frame which should clarify what I am talking about.
Hope this helps.
Tom