G16 low end power, limit top speed

[Canuck12345]

Hello folk's, I believe I have a rather unique need to modify a G16 for use exclusively in rough/ hilly terrain while carrying an approx 150lb load at as slow as possible speeds.

I am hoping to get some advice on the best way to limit the top speed to as low as 4-5 mph (even less would be better), while having generous power to carry loads up a steep hill.
I know I am in for some clutching modifications, just not sure where to get the best outcome.

Here is where I am at now and hoping for advise on the most effective change that I can make.

The terrain is very rough and to gain ground clearance I am adding a 6" lift kit and 22" offset tires. Adding the larger tires will increase the speed and the load on the engine at engagement. This is not desired, but understandably a necessary evil.

I also have on order an 85+ Clutch Kit Sheave & Power Spring to modify the clutching and to bring up the rpm slightly in the lower speed power band.

If I could have everything (I think), I need I would like to have the clutches engage with the belt, stay engaged, but not continue to increase the final drive ratio by working its way up and down the drive/driven clutches.

I have a new belt on the cart, but it is not at the top edge of the driven clutch. Can this be changed to go to the outside rim of the driven? If so would a wider belt do it without dragging on the driven clutch at idle?

If I have been able to explain my need, has anyone got suggestions on the best way to go about doing this?

cheers