Has spark no start?

Hello, so you have spark, you're just missing injector pulse. Do you have power to the injectors? You should have power on one of the 2 wires to each injector. I know this only has a throttle body (TB), so there's only the two injectors in the TB. Here is a guide to checking the injectors. And does the truck start still with an alternate fuel source with the new PCM you put in? If so, go ahead and verify there is power to the injectors. With these older vehicles it may have a connector issue from the PCM to the injectors or power supply. The wiring diagrams for these are also not the greatest. I'm trying to find a decent one, but with the key on you should have power on one wire of each injector.
You can also unplug both of them and make sure they are both have the same resistance reading. Making sure one is not shorted out, since they are both going to be fired at the same time. If one is shorted out it can damage the driver inside the PCM. Fuel injectors are Ground side controlled, so the PCM opens and closes the ground wire extremely fast to pulse the injectors. And when they or one shorts out, there is excessive current flow through the PCM transistor controlling the injectors ground side.
One other thing is if the vehicle has not be running in a while, the fuel injectors might be stuck closed. You can try manually energizing them for a quick second, I have seen this method work with even just a 9-volt battery. You only need to put power to one side of an injector and tap the other injector pin with a ground wire and if there's pressure behind the injector it should shoot out fuel. Don't energize it for more than a second though, this test is just to verify they are not stuck closed.
There is actually a video of someone doing this, I would attach some wire leads to the injectors instead of just touching it with a 9volt battery, because you don't want to make a spark near a fuel source. So, make up a lead that can hook to the injector and battery positive and another that you can go from the other injector pin to battery negative and very quickly tap the ground to battery negative and it should activate the fuel injector. Here is the video of someone doing this, but don't do it the way he is, use some wire leads to keep any spark away from the fuel source.
The 2nd video is showing why a shorted injector will cause the other to not fire. Just to give you an example of how that fault can occur.

https://www.youtube.com/watch?v=eq00NtmsyTg

https://www.youtube.com/watch?v=3gTLY6vsxMg

https://www.2carpros.com/articles/how-to-test-a-fuel-injector

https://www.2carpros.com/articles/how-to-use-a-voltmeter

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

We can see your reply, so you have power to the injectors, and they both are the same resistance measurement? The next test would be with a test light to see if there is any injector pulse coming from the PCM, Hook a test light to battery positive and with the injectors plugged in back probe the control wire with the test light and have someone crank the engine over, you should see the test light flicker while the PCM pulses the ground side of the injectors. If there is no pulse, there is either a wiring issue to the PCM, or there is something going on with the reference signal that the PCM uses for the ignition system. The Ignition module controls spark on this vehicle, and the PCM sends out a signal to the Ignition module to control spark timing, but even if that signal is missing from the PCM, you can still have spark from the ignition module controlling it at base timing. You just won't have any advance.
For example, when you want to set base timing, you unplug the SPOUT connector and the vehicle runs at base spark timing, usually 10degrees, after you set ignition timing you plug the SPOUT connector back in and the PCM will advance the timing as needed. So it might be that you are missing that output.
The diagrams for this vehicle are the old style and not very good, but I'll post them for you.
This is the better of the two wiring diagrams, so check the wiring from the ignition module to the PCM and make sure you don't have any corroded connectors or broken wires. You can see that the ignition module is completely in control of ignition spark if the timing connector is unplugged. This is because the pick-up coil goes to the ignition module first and then outputs it to the PCM. This is a very basic system. So, check all the PCM grounds for corrosion as well. With an older vehicle there is bound to be grounds that are not in great condition.
You can check grounds with the key On and a multimeter set on DC volts, check from battery negative to the engine block, and to the body/frame for any voltage drop on the Ground side of the system.

Here's a great video on ignition modules and he starts out with the GM system. It helps to explain how you can have spark but no injector pulse. If the Reference signal is missing.

https://www.youtube.com/watch?v=_Ijhi7ai1HY