you will want teak one side plywood exterior marine most of the over glass stuff was 1/4".
make tenplate on one side use door skin to do this as it will keep so you can flip it and make the otherside cardboard gets to beat up and will not hold up. I like to put white shelf paper on the teak side to protect the wood while I get it in place and glued down with a good epoxie glue with at an eight hour set time for strength. use allot of one by two to put pressure on as much of the surface as you can. Clamps around port cut outs and where you can clamp it down. Tight man thats how you want it and clean up the ooze right away don''t let it set up.Now do the other side the same way. Who ever said remove the paint was right on get rid of it. Ok now you have the clean wood in place and you did not leave the contact paper on for three weeks did you??? good don''t do that take it off as soon as the wood is in place or the heat and moisture will leave the glue behind and it is a real bummer to sand off.Now you have a clean and undamaged new teak cabin you can varnish three times a year thin that first coat real good so it gets in deep. Don''t sand to much or you will have a botched job in a hurry remember the vanier is 3/32 or some times less thick some may be thicker shop around on the web you may find some that is a bit thicker for exterior service. You may need the long grain 10'' ply if you have a long cabin it is worth it when done the trim is a job you may need some wood shop to cut or rouder the pieces for you measure it several times before you cut it shrinks and grows with out warning and you cant strech that $50.00 piece of teak even a quarter inch thats just crap. And they want the same price for a new piece after a couple of hundred dollars they should feel sorry for you right
Buying the wood with long grain and clean for the cabin can be a chalenge but some sites have full descriptions of the wood they sell even photos.