Timing suggestions for 360?

I have a magnum 360 that I'm going to be firing up tomorrow and looking for some ideas on where to start for setting the timing.

Its very similar to the MP 380hp crate 360 magnum with a slightly smaller cam

-Stock heads, internals
-Holley 650 CFM 4bbl vacuum secondaries
-MP Electronic Distributor w/Vacuum Advance
-Air Gap Intake manifold
-Intake .487" lift 231* dur @.050 Exhaust - .497" Lift 234* dur @.050
-Dynomax full length headers
-2800 stall
-3.91 gears

Also, how do I go about setting the total advance with a vacuum advance distributor? Is that possible? thanks