Re: Starcraft 1985 FM-160 Interior Overhaul
Welcome to iboats!
It's a typical Starcraft fix
First....your transom DOES have wood inside it

and it is also easy.
You are going to have to remove everything. All the screws and drill out all the rivets. Your carpet is bound for the trash bin ..... there is no saving carpet.
Look at all of the Starcraft restorations going on. Once the seats, console and side panels are out you have to strip the carpet..... expose the wood.
Locate all the screws and rivets..... drill the heads off the rivets and pull the wood panels out. You need to duplicate the wood panels with 1/2" or 3/4" exterior plywood (with at least one side finished but not necessary) DO NOT USE Pressure treated wood...it will react with the aluminum.
Seal the plywood up on both sides and all edges and re-install with aluminum pop rivets and/or stainless steel screws.
Re-install new carpet or vinyl on the decking and you are done.
Do a search here for bole holes to see if your transom needs replacement too.