Carryall Jackshaft help

So I decided on swap a 420cc clone into my carryall. I know I have to run a jack shaft but I have seen 3 different kinds.
1. Clutches on engine side, sprocket on drive side
2. Sprockets on engine side, clutches on drive side
3. and sprockets all the way around

Which method is the way to go? It seems like sprockets all around don't have to worry about belts slipping easy gearing change and way cheaper. But if not what clutches do I need? If sprockets are the way whats the gearing I should shoot for?

I know its kinda off topic but how do you guys hook the throttle up to the stock pedal?

Thanks