Thanks all! You guys are entirely right, I was not getting a tach signal. After some further research, I found exactly which was the test tach lead, from there, I tested it with a multimeter and no voltage.
I tested all of the blue wires from the distributor wiring (this was an engine swap that I didn't do, I just bought this car)
There was one with voltage when the car was running and I test ran this to the B8 pin and wa-lah, I had a tach.
I then ran a wire to the test tach lead, which also turned on the tach when the cluster was plugged in.
So thanks everyone and hopefully this thread helps others. From my searches, I found the tach wire, the distributor wiring, the color of the wire, but no one had a similar issue of when you plug and pray and the cluster didn't work.
So the extra step here is to test for voltage first....