Electronic small block distributor

Yeah, this was used on a Megasquirt system, so I think that was the intent. This was effectively used as a cam/crank sensor, so the advance was all done in the software tuning, not mechanically. Nice to know what it was actually originally used for though. Could a vacuum advance be added? Looks like the black plate on the side might have covered the original cutout for an advance mechanism, but I suppose the internals of the distributor might not support it and it was just a common casting they were reusing.