Hello, installing a leaning post on the 2003 bay stealth center console in my message signature photo. I have read about using a backing plate for the feet but that is not feasible for this boats design. Would it be a bad idea to mount with stainless screws directly into the floor with no backing? Floor is in good shape so I do not see any problems there. Leaning post allows for three screws per foot. Thanks in advance for any advice.

Dave,

Mounting anything with no backing plate never ends well.
If it's an aluminum floor, the screws will tear out. Been there, done that with a Fishmaster top on a G3. As an example, if the floor is .125", a 1/4-20 screw will only have 2 1/2 threads holding. It doesn't take much force to rip them out. That's with threaded screws. Sheet metal screws will be worse.
If you can't use backing plates, I wouldn't do it. You will spend more time fixing tan fishing.

Just screwing in stuff to the deck never has a happy ending.
You'd be way ahead if you cut a round access port, then install backing on your seat.

Thank you for the advice. I was considering giving these a try as a pseudo backing plate since the hull is completely filled with foam. Any experience with these?
http://www.garelick.com/productsearch.php?pnumber=21026&subid=EB06

Man, I don't know about those on a leaning post. I have them on a few rod holders on my gunnels and they do well for those. For reference, my gunnels are 5/8" thick.

Not for a leaning post. Not if you want it to last a long time.
If it were mine, and I really wanted a leaning post installed, bite the bullet, cut a access panel you can put a screw on lid on, scrape out foam and do it right. AND by all means seal your holes, and screw threads when you install. VIP's I've seen all had plywood floors, so you gotta be vigilant and seal them right or it'll cause problems later.

A 6" inspection plate with a screw on lid will give you room to get your hand in. You could probably get by ith large fender washers for backing, but since you have to cut the hole anyway, the preferred method is to fabricate a backing plate of 1/4" aluminum the same size or preferably a little larger than the footprint of the leaning post. You won't have to remove enough foam to cause a problem.
Do it right so you don't create a maintenance problem that won't go away