The first thing you need to do is draw a rough sketch of the inside of your boat... then draw in what components you want in it. This will help you decide how much room you will need for storage, where to run your electrical wires, and battery placement.
If the boat is a 1232 (32" is the inside floor width), you won't be able (in my opinon) to deck it... you'll only really be able to put a floor in it. If it's just you fishing in it, you can stand in the middle between the rear bench and middle bench, but that's about it. Storage will be slim, but you can cut out the insides of the middle bench and use that. Then mount you a permanent seat in the front floor. For this I would recommend using 15/32" exterior grade plywood (non pressure treated) mounted directly to the ribs.
If you have a 1236, you have a little more flexibility, but not much. I did this conversion a few times and the best that I found to work was a flat floor in the middle between the rear and front bench, then raise the front deck to be level with the top of the middle bench seat. Any higher than that and you're liable to do a topsy turvy when you get out to your spot on the lake.
Once you give us a few more specifics of your boat - make, width of floor and across the gunwhales... what kind of livewell you're looking to put in (permanent or removable - like a cooler).. we'll be able to give you some more guidance
Welcome to the site!! :beer: