An important side note on the machining of the Equalizer Bars, is that one needs to account for the internal stresses of the metal being released due to the machining process. If one is to machine the bars without accounting for the internal stresses, the locomotive will not equalize properly as each equalizer bar will have slightly different dimensions in key areas.
The dimension is that between the top of the bar, which is the reference surface, and the feet. The springs apply pressure on the reference surface, and the feet transmit the spring tension to the axle boxes. Obviously, it would make sense that each bar have the same dimension, or reasonably close enough as to not cause issues. The feet must be machined last, as each foot will have slightly different deflection from the stresses of the CR steel. Indicate off the fixed jaw of the milling vise which is against the reference surface, doing final machining of each foot at the same distance.
After all the Equalizer Bars are machined, place them all upside down on a flat surface, against the reference surface, you should be able to run your finger across the feet, and they should all be the same or close enough.