They used to slap gel coat over plywood in the 70s and 80s...... Basically all the rotten boats
It's not a good idea
Now, cover the plywood with 1.5 oz cloth, make smooth, sand smoother, apply gel, polish. It will last a fair amount longer
Mahle is GMs vendor for many internal engine parts.
Remember, the motor is a GM truck long block with marine gaskets and Mercruiser exhaust and accessories
Summit Racing and rock auto both ship to most countries in Europe. Usually faster than I get parts in Florida (3 days to Scotland, 4 days...
Not needed. Rebuild existing transom with AC. Plywood, make sure wood goes to the edges. Laminate the two pieces with tite-bond III.
Seal the wood with Rust-Oleum
Drop in place, replace the transom cap
history lesson on the "vortec" name. for many years, GM (and many others) did not want to pay royalties to Sir Harry Ricardo for the better combustion chamber shape used today.
Vortec was a sales name given to the V6 about 1985 when the 4.3 was released. as Scott mentioned, the heads came in...