Set up the front disc & caliper. It's going to work, but there's a lot of messing around to get things right. Lots of little stuff needs to be done correctly, but it's going forward. This is a shot of things in place & rolling without any drag.

1 - OK, so here's what it took to mount the brakes. The front hub flange was too wide, hub flanges were reduced in width on the mill (see above image).
2 - The axle for the rim is 12mm in diameter, but the forks are made for a 15mm axle. Bushings were made to fill in the difference & used to center the hub in the forks.
3 - The brake disc is a different design (flat, not the original "pie-shaped disc"), the new disc is a large diameter (220mm). To attach the disc, the holes were "stretched" from their centers a few hundredths to fit the holes in the hub.
4 - The hub's holes were counter-bored a bit, so the screws would sit into a small recess to allow the shoulder of the screws to sit tightly into a recess for each one.
5 - The caliper didn't match well with its original bracket, so new holes were drilled & tapped to offset it about 0.40" inboard, to match the brake disc & its location.
6 - Also due to the offset of the hub, a shim was made to slide the caliper toward the center-line of the hub a bit (1/4") to keep the pads from dragging against the disc on the fixed side.
Progress is being made, but this is a different set of tolerances than I usually have to deal with, so I'm a bit slow in figuring things out & getting them done.