Alumacraft MV 1648 NCS Questions

Was planning to do some modifications and was wondering if anyone knows what they have used for support under the front deck of the boat. Do the back covers behind the back bench seat have floatation foam in them. I have contacted Alumacrat several times and can't get an answer.

https://www.tinboats.net
Go over here. Bet you can find any info you need. Interesting site.

I have a 2012 alumacraft 1648 under the front deck is plywood and the rear bench seat and rear covers all have flootation foam inside them, hope this helps