Transom Recore Liberator 261 Tips welcome

Have not used this boat in the last couple years, as it leaked in 2007 when I put it in. Found out I had a transom problem after checking everything else. Current status both engines & drives pulled, all transom hardware pulled, inner transom skin removed, and plywood almost completely removed at this point. Getting ready to recore with plywood, as this is my 1st attempt at a boat repair like this I am looking for advice.
This boat has both through transom and prop exhaust, has been modified for the cutouts. My plan is to use epoxy for the wood to fiberglass bonds and maybe polyurethane PL stuff between the ply sheets. Thinking of using 3 layers of 1/2 inch as it would make the fit behind the stringers go a little easier.
The tear down was quite a bit of labor as the wood was solid but wet at the bottom of the transom and the stringer cores looked OK not too soft. With the heavy glass on the stringers, I would be reluctant to cut them out anyway.
Any tips welcome as this unexpected project is taking too much space in the garages. My typical use for this boat is to leave it in the water for the summer thanks for any help.

 

There are many previous threads about the tasks you're undertaking. Use the search tool and waddle through the dozens of earlier posts. Use epoxy between the plywood sheets, there's no economy using PU and you'll have the epoxy on hand anyway.

In one of the previous threads on this subject, you see a sketch I made for a three plywood sheet lay out of the in a transom. Considering your twin engine install, you'll likely need the additional strength it provides.

 

three plywood sheet lay out

Thanks for the tip on the layout, had not even thought of that, will plan on using that approach. I like how simple your sketch depicted that.