Well I finally did it. After many years of searching, and after asking many many questions on this forum, and then mentioning I was boatless (to which you guys were probably wondering why is this jerk asking all the questions), I finally bought a boat!!!
I am pretty sure its a Peshtigo built 1965 Thompson Off Shore, 20'-1" center length. In a previous post I learned a bit about the number stamped in the transom, however I have not found the metal plate to verify the model and location built. The previous owner started to disassemble the transom so I am not sure where the plate might be.
Here is a picture, I hope that it comes out. I will send more if this works.

The story is somebody trailered the boat from Michigan to the Rochester NY area, where is was sold again, then I bought it, so of course no registration on the boat or trailer.

It seems to be in very good shape in terms of rotted wood. However I plan to flip it and do a full re-fasten and replace things as needed.
First restoration question. I need to build a new transom and the old one has been partially disassembled. I am not sure all the pieces are there, but the inside pieces that screw to the strakes are still in tack to give me a pattern. If I build the 'outboard' side of the transom with horizontal pieces of Mahogany, are there pieces of mahogney laminated vertically on the inside across the entire transom? Or just the outer perimeter of the transom and where the motor goes, sort of like the picture from a very recent 'Transom Construction' post. If anyone has a picture of the inside of their transom from a boat of this vintage, that would be appreciated.
I am considering putting a newer power source on it like a 4-stroke. Really heavy, is there a benefit to making a transom 3 layers thick (I am not sure how thick each layer of the transom is (3/4" or 1", havn't measured yet). Then adding metal supports to the transom with through bolts through the transom. I am not sure how the original knees would have been attached since they have been taken off already and I have not found them yet (they are probably laying inside the boat someplace). Didn't know if the knees were screwed from the inside of the boat, through the knee and into the transom. This would seem to make better structural sense as oppose to going from the transom into the end grain of the knee (assuming end grain touches the transom)
I have other questions on which order to insert the new transom, fix ribs, garboard planks, re-fasten, when to bed with calk/adhesive, but I will wait for another post.
thanks!!
I am very excited to start working on her and get her in the water!! Its my first wood boat and my first boat of this size.
Regards
Peter