First off, remove that hold down clamp and grind that tooth off of it. That's a LA TBI or Magnum EFI clamp, designed to PREVENT the distributor from moving- on those motors the distributor is used mainly to reference the fuel injector signal- ignition is handled by the computer. Your application needs full range of adjustment.
View attachment 1716304595
Secondly, don't worry too much about which bolt the slot in the intermediate gear is pointed at- that generally applies to stock distributors that have proper blade/rotor indexing, so the vacuum can will not interfere with normal adjustments. Yours is obviously not stock (no vacuum can), and aftermarket distributors rarely have the proper drive blade to rotor relationship anymore, anyways.
So; set your timing marks at about 10-15* BTDC on the compression stroke, and adjust your distributor so the reluctor wheel is just beginning to align with the pickup. Then, wherever your rotor is pointing is your #1 terminal on your distributor cap- install the rest of the wires from there.
If all is well with the rest of your setup it should fire right off the bat.