I've already got the freehub outer shells switched out following the directions on a Youtube video by "RJ the Buke Guy". Everything worked out fine except - like I said - the right UG cone is too large in diameter for the HG dust seal (which you have to use because the HG freehub has internal lockring threads). Either you have to find a right cone (of the correct diameter) off of a HG rear hub or you have to enlarge the inside of the dust seal so it fits over the UG cone (or you have to do without the right dust seal). I'm leaning toward the latter option so I don't have to look high and low for the correct outside diameter right cone unless someone on the board here knows where I can still get one.

Except for the notches in the cassette lockring for the removal tool splines the inside diameter of lockring is so close to the outside diameter of the UG cone that it's tempting to just do without the right side dust seal. This is a road bike so it's not like a mountain or cyclocross bike that's going to be around a lot of dirt.