Got fuel, spark, comp but no start

I've seen that, too. Dead spark on start circuit, when crossing back over to run position on the switch.

Maybe just an oversight, but have you checked your distributor against the cam, itself? Not the drive gear or rotor position, but the rotor position against cam position. Lots can happen between the cam and distributor on assembly.

For what it's worth, when the timing gears are set with the dots facing each other, instead of both facing up, the distributor gear slot is the same, but the rotor is actually at the firewall.

To check it easily, take the cap off of the distributor, pull the #1 plug and crank the engine a touch at a time by jumping the relay terminals, until you can feel pressure. As soon as you feel pressure, the rotor should be approaching the #1 plug wire terminal position on the cap.

That's the quickest way I know how to find true #1 position. Even if it turns out to be something else, it's peace of mind.