Thanks, Garth -
That's a Duraspark II ignition module.
That one is a "Eichlin" (NAPA) version, but they are all about the same - from outward appearances.
Engine should be going in shortly - possibly this weekend, but if not, but the end of the week, certainly.
Just to whet your appetite, here's a picture of the "outboarded" Compressor / Alternator setup that Wade (4280 / Mark IV) fabbed up.... Still needs a little adjustment work on the Alternator Tensioning system (minor challenge).