I think the OHV is stronger and better than the SOHC. You get better gas mileage too. Direct replacement. Why do you want to change to a higher revver for power? You getting the newer model cheaply?
And I am saying yes to the wiring harness. Fuel amounts, timing, etc are going to change between the models. Every swap I've done required a new harness, although they weren't on rangers.
Pete
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