Looking for help with timing ignition in Calgary

Have to admit - I am close to zero when it comes to older distributors, setting ignition timing and other wizzardry from the era that predates electronic/plug-and-play tech.

Now, being in the final stage of my Sniper EFI saga, I encountered a situation when I need somebody fluent in the above stuff.
I am sure I screwed the distrib timing since the first attempt to start (after all the presets were complete) ended in backfiring into the intake.

I wonder if somebody could stop by for 30...

Looking for help with timing ignition in Calgary