No Spark...?

[RMrider17]

I just did an engine swap on my '85 2wd C10. It started life with a '85 305 and now has a '86 350. Everything is hooked up to make it run for a test fire:
Block, Heads, Intake, Carb. Water Pump and Alternator.

We went to try and start it and it cranks normal but has no spark. We checked some wiring, but may have missed something, 4 prong wire on back of distributor is hooked up. The Battery line to the back of the distributor has power, and the other line into the distributor with the 3 wires is hooked up. Checked ignition fuse and it is good.

I tried swapping a few parts that just came off of a running car: Cap, Rotor, and Coil, but still no spark.

Does anyone have any idea what my problem is? and am I right in thinking that even if the distributor was out of time it would still spark, just not when it is supposed to?

And the distributor came off of the 305 and it ran, however it did sit around for a week, and could have rolled around some.

Thanks, sorry for the long post
-Adam