Let me see if I'm picking up what you're putting down and we'll go from there...
You have a programmable ignition setup and, if I understand them correctly, most of those boxes/distributors work by taking timing out instead of adding it. You need to lock out the distributor at 40 degrees and your programmable ignition box retards timing to get it where you want it to be, since the ignition box needs to have an event to trigger it ahead of the earliest it will fire.
Is that the general gist? Or do I need to do some reading?
At any rate, in addition to the info we have, your compression, fuel, what heads, and converter would help get you a starting point for a timing curve.
