Please help, crank, no start

I know I post on here quite a bit but I really need some help this time, I just recently replaced the motor in my 91 LS-S but upon trying to start it I have a crank no start issue. I looked at the ECU to see if there is a code but there is no activity coming from it. I swapped out the distributor with a known working distributor and still no spark, the timing is set to top dead center and it is wired correctly. It seems a little weird to me because I had a horn one minute but the next time I hit the horn I had no horn what so ever, also I have no fuel pump, it was the same with the fuel pump as it was with the horn, I had it one minute but the next nothing, as I stated all I did was swap out the old motor for the new one, nothing changed, should I swap out my ecu and see if that helps, I’m at my whits end. Please help me with this, I’m about to take my gun and just start shooting holes in this car.

You should get the multimeter out before shooting the car…
Check that there’s power at the starter. If there is, try jumping the posts of the starter with the car in neautral or park to see if it will turn over. If no power and no turn over, you need to recheck the wiring.
Quadruple check your grounds. Don’t forget the one on the thermostat housing.

Post results. Maybe even snap some pictures. Check fuses etc…

Stop! Don’t shoot!

Yes there is 12.6 volts at the starter before cranking, the car rolls over like it wants to start but there is no spark and no fuel, I made sure all of the wiring is connected properly

So the fuel pump doesnt prime? Could be the main relay maybe

Thank you guys for helping me with this situation, I figured it out and it wound up being one single wire that was not hooked up and I simply over looked it

HAHA!!! That is EXACTLY what happened to me, the ground wire near the speedo cable on the tranny was not tightened down and the car gave the exact same symptoms you gave. Glad you figured it out!