Your fuel selector valve has rubber "O" rings inside of it that seat into a groove machined into several places on a shaft with holes drilled into it. This comprises your your fuel selector valve. These rubber seals eventually wear out, crack, or break, & need to be replaced. It's not hard...
You can but, it'll be expensive... Why not buy a good used Yamaha C3 Scooter (called the Giggle and Vox in other parts of the world.) It already has electronic fuel injection, with a computer and all of the same electronics that modern automobiles possess. Mine runs 46mph ang gets 117mpg on...
I'd go with the Toyota. The main reason being that Jeep's Owner is financial disarray at the moment closing dealerships and assembly plants.... You might go to "craigslist," or Ebay Motors, and see what $4K will get you.....