Trying to resurrect a Magnum, 360-2, electronic ign. conversion done. (orange box)

Bought it with engine partially apart. Installed intake and carb, and have had it fired a couple times since the intake and carb were reinstalled.

OK, tried for grins to start it today, no fire (or appears so) It had an aftermarket tach that dropped below zero today while cranking.

What/where/how do I test for spark? What's first to check?

Yes, it's getting fuel.

well the most fundamental would be to pull a plug wire and put another plug on the plug wire and ground plug to intake and crank over. If no fire then check pos. side of coil with key in run position , u should have + - 12V there.
make sure new box is grounded.
get that far then we'll move to the next step

It has an aftermarket coil. The ign. conversion was done prior to my buying it, and has been on it for some time.

I"ll try that next time I'm out in the garage fiddling with it. Thanks

For the night shift

OK, I have spark, and it's getting fuel. the spark was "orangy". Isn't it supposed to be blue?

Take off the yellow "ign" wire off of the starter relay to disable the starter. split the dist pickup 2 wire pull apart connector and tap the male end of the eng connector half to ground & see if that makes the coil to dist (dist end) wire held 1/4" from a ground produce sparks while a helper holds the ign key to "start". If so all is good ex the dist pickup or it's wiring. If no spark plug the connector back together and take off any/all wires from the coil negative primary terminal and w a jumper Morse Code tap the coil male neg pri terminal to ground as the helper holds the key to "start" and if this now makes the center coil secondary wire spark then either the dist pickup, the ECU,their wiring or the ecu ground is faulty. If no spark either the coil or the ign sw "crank" ign2 terminal/wiring out to the coil positive pri terminal starting w the bulkhead has an open. Holler back & we'll go from there