Lean Burn Dist
If you take a lean burn distributor and combine it with a performance electronic you make a mechanical advance electronic.
You would put the lean burn fixed pick-up plate and the cover plate used to cover the Vacuum advance access hole. This also has the tab for the cap.
You will now have a mechanical advance distributor without the vacuum advance hanging on the side. It will look like it came that way and gets rid of the clutter of the advance. The motor pictured below has one installed