Transom/floor questions on my 20

[Basketcase]

Hey all. I'm finally getting a chance to work on my old potter 20. Today I installed and tabbed in the transom with 1708 and was able to get one layer or 2408 on the transom as well. I have some questions about the floor and transom.

On the transom, I was thinking that 2 layers of 2408 would be enough but I want to be positive. I'm doing a full transom for a bracket. 2 or 3 layers of 2408?

For the floor should I use .5 or .75" marine ply? One layer of 2408 on bottom and top enough? I am using 2408 because I have a 4 foot roll about 18" in diameter that I got on craigslist for 80 bucks so I'm using it!

I'm also raising the floor a few inches. What do folks usually use to do this? I got a beautiful clear fir 2x4 for the center "stringer" and thought of getting more for the floor but the stringers are slightly wider than a 2x4. I was thinking of laminating layers of .75" marine ply, using 4 layers to get the height I want. Another option is to cut the 2x4 to the width of the stringer and use 2 of them since I'm hoping for around a 3" raise.

I love looking at all your projects and appreciate the help with mine!!

Adam