I took the uprights and hubs to a local machine shop and they came out great. As you can see in the first picture a large rotary table was used to remove the lip on the upright that was preventing the hub from being mounted. A very small chamfer was also added to the opening so that the flange would sit flat. The four threaded holes in the rectangular flange were also drilled to make them clearance holes. The machinist said it was as tough as any metal he's ever drilled.
The housing that bolts to the upright has an electroless nickel finish that should hold up well to the elements. They didn't use nickel on the wheel flange because it would have changed the dimensions on the bearing surfaces and masking was prohibitively expensive. It's a chromemoly forging and won't flash rust like a mild steel part does. I'll just apply some Boeshield T-9 to both surfaces.
I also confirmed that there are 47 teeth on the reluctor... the primary reason for upgrading the hubs.