Hey everyone I'm new to the forum and got some questions for my first time build on a surface drive. Any help would be appreciated. I have a Honda 13hp GX390 I got for free and want to build my own just as a new project as a challenge, for a 1436 Jon boat.

1) I know I want to use a timing belt set up, but I have no idea what ratio to run or what size pulleys to get that gear ratio or what size prop to run, what set up would be ideal?

2) it's going to be out of steel, I have no way to weld aluminum so that's out, what thickness would be good?

3) I'm kinda lost on the bearing and seal set up for the prop shaft ? any diagrams and parts list would be great to give me ideas,

4) what's a good length for the prop shaft?

5) what engine mods are recommended to keep it reliable, but just pep it up a little