The cushion spring bottom has two round wire tabs on the rear that go into slots in the rumble pan reinforcement triangle support. The front of the cushion is secured in place with two straps of matching seat material that go under notched blocks and then have eyelets that go over a double headed nail/pin. The straps keep the front of the cushion from lifting and the blocks keep the cushion from sliding forward. I have pictures but it will take a little bit to get them posted.
Chistech: Great detailed answer - no pics needed thanks. Another seat question: Front seat has a wooden base for the cushion spring. There are a couple of flat steel square hooks along the inside of the front member near each front corner. Can you tell me what they are for?
Those “hooks” hold the cushion from moving forward by fitting in behind the back edge of the seat frame’s front board. They basically lock the cushion into the lower frame. Another way to explain is those brackets are on the bottom of the cushion. When you put the cushion into the frame, you push it back until the cushion drops in slightly as those brackets clear the back edge of the seat frames front board.
Thanks Chistech. Very helpfull. Another seat question: Rumble seat backrest has a couple of tabs that I presume fit into notches on the inside top of the deck lid. Seems kind of flimsy (Snyder's spring). Is there anything else that should hold the backrest in place? Thanks.
There are two bolts at the bottom of the lid that hold the back rest in place on my 31. With the tabs at the top the back rest is secure. The attached picture shows the back upside down with the bottom tabs a few inches from each side pointing up.
