Sounds like a bad crankshaft position sensor except you don't have one.

Your computer takes a signal from the ignition control module on your distributor which uses the internal  pickup coil as a crankshaft position sensor.

From this signal your computer determines ignition spark timing and fuel injector pulse (which you have neither)

How it works: (source: easyautodiagnostics.com)

1. The distributor shaft starts to rotate, inducing the pick up coil to start generating its magnetic signal.

2. This pick up coil signal is sent directly to the ignition control module.

3. The ignition module, upon receiving this pick up coil signal (for all intended purposes it's a crankshaft position sensor signal) converts it to a digital signal that is now sent to the fuel injection computer. This digital signal is called the: Distributor Reference Hi Signal in the majority of the service literature.

4. Also, after receiving the pick up coil signal, the ignition control module starts to switch the primary current (of the ignition coil) On and Off. As you might already know, it's this ‘Switching Signal’ that makes the ignition coil start sparking away.

5. OK, once the fuel injection computer receives the Distributor Reference Hi Signal, it starts activating the fuel injectors and above 400 RPM, starts to send a 5 Volt Bypass Signal to the ignition control module. It's with the Bypass Signal that the computer starts to retard and advance ignition timing with the IC Signal.

6. So, then above 400 RPM (any RPM above this and the ECM considers the engine as having started) the fuel injection computer starts to control the ignition timing.

Here's a link to a 6 page easy step by step process to test the ignition control module and pick up coil 

https://easyautodiagnostics.com/gm/4.3L-5.0L-5.7L/distributor-mounted-icm-tests-1

There's lot's of stuff that it could be with the distributor/ignition system. Also, the mid 90's Chevy and GMC truck/suv fuel pumps were know to be a weak point. We went thru 2 fuel pumps in our '97.