Millennium seat questions

[E-Z Poleholder]

I have a War Eagle 861 that I replaced both driver and passenger seats with the SW100 series. Made a 1/4 inch plate about 12” square, bolted the seat to the plate, then when I had it positioned where I wanted it, I bolted the plate to the storage lid. Shimmed it up a little in the back to make it sit better. Rides good even in rough water.
Just got me an old Ranger 390V and took the bench seat out and replaced it with a carpeted 1/2 inch plywood. It is right over the tanks, just be careful with screws not getting into the tanks. This was easier bolting the seats directly to the plywood. Sits awesomely good, that boat rides good anyway. Used the SW100 seats here as well.

[skunked again]

CatchNgrease - Now that I think about it, never seen a production model boat with 3/4 pin bases for driver or passenger.
E-Z poleholder- That's probably how I should do it.

Y'all have given me something to think about! Thanks!!!