1. Is the spark a snapping BLUE
spark? Yellow/white/orange indicates a weak spark, which will not be strong enough to start the engine. Usual suspect here is the ignition coil. Your coil can be tested for both primary and secondary resistances with a meter and a manual.
2. If spark checks out (and only
IF) introduce a small splash of fuel into the intake or a short shot of starting fluid. If it starts and runs for a short time, you have confirmed a fuel delivery problem. For a 1990, you need 31 psi to start and run the engine. Use a fuel pressure gauge if there is any question.
3. What is the status of tuneup hardware? Importance of this absolutely cannot be overstated. Fresh Champion copper plugs gapped to .035, new plug wires, distributor cap, rotor, fuel filter.
4. Still stuck.....run a compression test on all cylinders. You should have 120-150 psi, with no more than a 30 psi variation between cylinders.
5. Here is a link to an article that shows you how to test many things on the RENIX. Should be a bookmark for all RENIX owners.