wood on Transom

Is it hard to remove? I want to sand the wood down and possibly add poly to it to shine it up, any suggestions, Maybe leave it in place and just sand it down in the boat? Its not in bad shape, just needs to be cleaned up, it is riveted into place

Just sand it and coat it in spar varnish or spar urethane.

Depends on the boat. Some are more difficult than others. On my boat, I had to cut the welds on the corner supports and remove them and then have them welded back on. Some you can simply drill the rivets and it comes right out. Whatever you do, be sure to use stainless steel bolts and nuts when it goes back on. Maybe its just me but if I was gona take it off, Id replace it. Depending how difficult it is to get off, you may consider going back with aluminum. Thats the one thing I wish I had done on my boat. The only wood on it is the transom and like I said, things have to be cut and welded for it to be replaced. Had I gone with aluminum, I would never have to worry about it again. If its simple to replace than go with wood for sure. Use exterier grade plywood laminated together with a waterproof glue such as Tite Bond III and a minimum 3 coats of spar urethane. I also gave mine a shot of walnut stain prior to the spar since bare plywood is fairly ugly.