how much initial timing mild 360 magnum

10* on the balancer is not enough.

IMO, you DO NOT need the timing retard module for start up. Period! That is designed more for distributors that are locked out at 30-40* constant timing and helps reduce the load on your starter. In many cases it makes the car idle HORRIBLE. I'd disable it and see what happens.

Time the car with 16-20 initial (on the balancer as you put it) and the rest in the distributor, 14-18, to get your desired total number of 34.