Re: 1971 16' starcraft supersport restore
The way I did mine (right, wrong or otherwise

...
Got a piece of ply and cut it to the shape of the entire bow. I then had to cut that sheet into about 2/3 - 1/3 in order to get the platform in and out of the boat (it tucks up underneith the very front of the bow). The 1/3 piece was the very front, the 2/3 piece was back toward the console.
I mounted the seat base in the 2/3 piece right in the middle, essentially in right over the bow "walk-way". I knew I would need extra reinforcement for the seat base, so underneith the platform by the base I screwed some 2x2 lumber where the platform "spanned" the walk way. i could still seat the platform flush on the seats as the "supports" hung low in the open walkway.
I also carpeted each piece of the platform with outdoor stuff.
The whole thing worked pretty slick. I had a bow mount trolling motor...the battery sat below the platform in the "walkway".
The only negative...if i wanted to ski or cruise with the ladies

i had to pull the whole nine yards out (battery included) as there was no place to store on board.
Don't know if this makes sense or not...
I do like the idea of the pole base in the floor and doubling for a table mount.