I figure 1 hour per run.

The easy way to figure it out is to track a couple prewires. Look at the amount of time it takes from the time that your workers clock in to the time they clock out and at the end of the prewire stage divide their time by the number of drops. Once you get that number add on 15-20% to cover any oddball stuff that may happen and I bet you come out to roughly 1 hour per drop.