no spark

Hook a temporary clip lead from a battery source to the coil + and see if you get spark

If not, inspect the reluctor and pickup in the dist. for damage, rust, debri. Wiggle all connectors in/ out to scrub them clean and "feel" for tightness. Inspect them with a flashlight for corrosion, other damage.

Hook your multimeter on AC volts THAT'S RIGHT AC volts to the distributor connector and crank the engine. The pickup should generate about 1V AC

Check the pickup for continuity. It should be open from either connection to ground. Actual resistance does not seem to be critical, somewhere from 200-500 ohms.

Remove and inspect the box/ mount for rust, clean it up, scrape the rear of the box ears, and use star washers. Consider adding a no12 or so ground wire from the block to one ECU bolt as well as the regulator

Put your meter on the coil and see what you have for voltage, key in run, as well as cranking. Cranking should be close to same as cranking battery voltage, and in no case below 10.5

Put your meter on the coil NEG terminal (or a test lamp is better) and crank. The lamp should flash, the meter should show rapid pulse.

Also try with key on, ground each ECU side distributor harness connector and check for spark. One or the other should trigger a spark.