... I have the 2 HP Doerr motor and factorymation sales support confirmed it met all the specs for the motor. I has worked perfect for 2 years now and no complaints. I wired a 3 way switch to it to control fwd and reverse to compensate when I change from High to Low. Like you, I took off the on/off hanging bar but left the original power switch on the side of the head as I like the way it looks. But I wired through it to the VFD and control the power with the 3 way switch I mounted by the VFD on the right side of the machine on an extended arm/platform that my mill came with...
The most significant thing I had to do was to replace the spindle bearings. About a year after I had been using it and was starting to get more in tune with the tolerances of the machine I started taking measurements and unfortunately noticed that I had 2 1/2 thou (.0025) run out at the base of the spindle. I could actually move the spindle by hand with an endmill mounted (not powered of course). So I ultimately decided to have Wells replace the bearing and the reground the R8 inside taper as well. Got it back and the runout was at 2 tenths (.0002) which is right at or better than the spec so this was quite a relief. It cost ~$900 but shipping was $150 of that...
Lastly (for now), I have just completed removal of the head and pulled all of the auto-down feed gears and cleaned then reassembled. I recorded as much of the process as I could and am still in the process of editing the footage into something I could post as a reference to others down the road.