Before I shortened the slots on my distributor it ran my vacuum advance through the manifold. It seemed to work just fine. You can adjust out most of the idle issues by adjusting the vacuum canister with an Allen key. Another idea to get rid of idle issues is to put a single light spring in the mechanical advance plate. This will allow full advance at idle because full advance comes in at around 600 rpm, give or take. This will also take care of your hot start issue of too much advance at start up since it cranks with only a few degrees of timing.