Help. I just bought a boat and i have a few questions.

I just bought this 14footer with a 1955 10hp johnson seahorse. First thing there is still gas in the tank from last season i'm assuming. Should i just get rid of the gas and if so how do i clean the tank or is that even necessary? Second the middle seat is not screwed down, and i'm not so sure how well the other seats are either but at least they don't move around. How should i go about reattaching it? The other seats are screwed down with the same hex screws. Do you think they will hold if i mount some of those sliderg5's to them. See pictures. Thanks a ton for any help or advice you can give me.

shoot, my picture files are too big.

I have the 1956 Johnson 10 horse. You can see my resto thread in my link. Theres lots of info about those little motors in there. I wouldnt worry about cleaning the tank unless it has rust in it. I would definately get rid of the gas thats in it though since you dont really know how old it is.