exhaust backfire

Im lost, the OP is triggering a Hyfire box with a points distributor?
If so, that dont sound right in any world.

No, the points distributor can be used all by itself with a standard coil as a test to get it to run without backfiring.

An old 60s 70s thing, one hot wire and you are running. (as you probably know).

He has a spare points distributor to use for the test.