how much initial timing mild 360 magnum

How are you planning on adjusting the mechanical advance in the dizzy? What distributor are you using?

I run 16* initial in mine with 22* in the distributor. 38 total

I can't believe anyone still uses that MSD junk. Buy multiple boxes and have to wire all this crap together, mount it, collect pills (or get an expensive box with some dials on it and mount that too) and then if it has to come out of the car, you have to either completely uninstall it or cut the wiring.

This Mallory Hyfire box is the shiznat.

http://www.summitracing.com/parts/MAA-685/

It has two step and high rpm rev limit, start retard (that only takes timing out during cranking and you can take out however much you want, not 10 or 24 like MSD), and window switch for nitrous (or high RPM timing retard). It also has a built in boost retard that is adjustable in 1/2* per pound of boost increments -but you have to buy the MAP sensor separate.

Its one box to wire in, has a weatherpack if it ever has to come out, no BS pills - all digital, and it costs just a little bit more than a plain jane 6AL. As an added bonus its quieter than the MSD junk.