I want to make one of these but im not sure how to make it. Last year I had some 1/2 plywood left over form the hurricane season so I made a deck for my boat and it came out real nice.So I know I can make one if I only knew how to make it firm? So I guess my ? is can someone tell me how they think the trolling motor deck is being held in place?

I have a Bass Tracker Tournament V-17, I replaced that top deck when I put a new trolling motor on because it was rotting out. The deck was bolted to 4 metal pieces that were either welded or rivited to the hull (can't remember and either would work). The pieces were a piece of metal bent into a right angle with one face attached to the hull and the other with holes for the bolts.  My trolling motor is also anchored to two of those pieces as well as the wood itself.  I would recomend either marine grade plywood or treated ply wood at the very least, probably 1/2 to 3/4 inch.  If you do a google search for boat rivet repair there is a tool and rivets you can get for about $20 that should work well or either weld or have someone weld the metal pieces to the side of the hull.  Should have taken pictures lol.