I'm confused, his 6500 LP is going to be the same split phase as the 8000. My 5500 LP was split phase. Any 50A service MH is already going to be prepared to accept the split phase. The wiring to the transfer switch is already sized for two 50A legs, so the only wiring upgrade will be from the gen output to the transfer switch - wiring which the gen probably already comes with.
The 8000 we have now is a water cooled variable speed pure sine wave generator and works sweet for us in our MH, but we also never had trouble from our 5500 LP in the 5er. It served us for 12 years in 3 different 5th wheels. What kind of trouble are you having?
