Transom Question

I just recently picked this boat up which is my very first tin boat and I have been reading alot of threads trying to get some ideas. I do have a question about possibly replacing the transom wood and was hoping to get some suggestions from you guys. The boat is an early 80's Sears Game Fisher 12' boat. The wood on the outside of the transom is showing some wear and I was thinking about replacing it. I was also thinking about replacing the wood on the inside and possibly making it stronger. When I turn on the trolling motor (Minnkota 50#), I can see the transom flexing. Would it be possible or advisable to drill out the rivets that are holding the aluminum channel which holds the approx. 6" wide board on the inside of the transom and replacing it with a full length piece of 3/4" plywood? My plan was to make the wood full length for more support since I don't have the "L" type bracket from transom to floor. If I do it, I was going to replace all of the rivets with 1/4" SS bolts or screws. Once the wood is in place, what would be the best way to seal the bolts or screws with 5200? One thought was to set the bolts or screws in place, sealing them with 5200 and then slotting the plywood so I could slide it in place, otherwise I don't know if I would be able to get the wood into place without slotting the wood. Any suggestions or thoughts would be appreciated. Here are some pictures of the transom and boat. I thought it was a decent deal for $350 as it sits with battery, trolling motor, brand new fish finder, seats and all. Tahnks in advance.

I would replace the inside and out with 3/4" non treated ply.. on the inside, I would go down farther than the 6" that is already there. I don't know how the guys have done that before, but I've seen pictures on here where they have slid it up into the aluminum channel - I just can't get my brain around how to explain to do it.

I would seal the wood (both sides) a few times, then put it in place. Drill the holes, then take a smaller brush and paint inside the hole with the sealer. Then use 5200 on the screw, and some squirted inside the holes before I put the stainless steel bolts through.

I think you are on the right path though

Cool, that's kind of what I was thinking of doing with sealing the bolts but I just wanted to make sure and get some reassurance. I'm thinking of taking the wood to just above the drain hole which is gobbed up with sealant from the previous owner and the bolts for the transducer. I really don't have any plans of adding a small gas engine because this is primarily used in a gravel pit behind my family’s farm where no gas engine has been in it to this date and I would like to try and keep it that way. The water is so clear that I can see the bottom in 8-10 ft. parts. However, I usually go overkill on most things and if I ever did get a little engine, it would be able to handle it. Thanks again.