forward cast platform removal

[Tashmoo2]

I was reading thread showing the Lefty Kreh edition Seacarft with coffin and not forward casting platform.

Other then a storage compartment for the anchor and life preserver it is really not useful as a casting platform.

I just replaced deck from stern to the platform in my 18 ft Seacraft but left the hull liner intact

Question; I have to use the existing inner hull but do not know an easy way to maintain the inner hull shape all the way down to the deck and to fiberglass it to the the existing liner.

Is it worth it?