854 back rest project

Some say the 854 had a factory back rest, if it didn't so be it. My 854 has one, and this is what i did.
I bought two one foot by three feet pieces of 1/8 in. ash hobby grade plywood. Then cut to a rough 8 in. by 1 foot size and glued four pieces face to face with lots of wood glue. Then clamped the 1/2 in. piece to a curved concert garden border section with every clamp and vice grip I had. Let it dry over night, when I removed the clamps the plywood retained the curve. After making the back rest pattern on paper I traced it onto the plywood and carefully cut out the back piece. Then located the attaching holes , installed the recessed 5/16 in nuts. Finally put two coats of sealer on to water proof the plywood. I don't have the know how or equipment to do the vinyl cover so I took it to my local upholstery guy and he did the covering. The finished back rest has 1 1/2 in of dense foam with a marine grade vinyl. the overall size is 10 in. wide by 7 in. high and 1/2 in plywood with 1 1/2 in. foam. It is comfortable and looks good on the 854.