The straps come as a casting, and have to be split, and then the mating faces machined before bolting them together. They can then be faced to thickness and bored out to fit the eccentric sheave jig.
The machined Eccentric straps.
The back faces were also cleaned up using the rotary table and the wheel jig with the eccentric sheave jig attached to it!
Another older shot of the axle boxes and axles before assembly.