Had a brand new MSD box that didn't even make it out of the gate.

So The coil fires when you jump the violet & green wire. That proves your wiring & box are good. Next step is to verify the distributor will trigger the box.
Set-up the same test but leave the distributor violet & green wires connected. Pull the dist cap & rotor. Loosen the distributor hold-down so that you can turn the housing. Then rotate the housing so that the pick-up coil moves across one of the teeth on the trigger wheel. The MSD should fire the coil every time the pick-up moves across the trigger wheel.
If you position the dis pick-up & trigger wheel properly, you might be able to use the distributor advance to move the trigger back & forth across the pick-up. Coil should fire every time you do this.

UPDATE:::::

I swapped in an MSD distributor and it fired right up. My best guess is there is not enough resistance in the factory distributors to trigger the box. Before the swap I ran my meter across the leads and read 525 ohms where the factory one read 287 ohms.

Sounds like the pick up coil in the distributor was bad.
I ran my car for years with an OE distributor and a digital 6 box.

But that distributor worked excellent in my other car. As its back in there and running.

Dont know what to tell you.. I never ran a digital 6
but have run plenty of stock dist with 6al and 7al
boxes.. both lean burn and dist with timing... so I
would think that the digital box doesnt like something
about that dist.. might be the difference in the resistance

Thanks for all the help everyone! 🚗 the old girls is running pretty good. I think my neighbors are already sick of my playing with the 2 step in the driveway.

Dunno man. Stock distributor should run with the digital 6 no problem. But hey, whatever works! Enjoy your ride