yep it's that little funny looking can thing on the 2nd pic right next to the alternator or under it and then next to the valve cover. I would remove it all. You got headers it's doing nothing as is, unbolt that sucker and trash it.
As for the vac. I forget buddy I got them same edelbrock carbs I'll have to check. I got one on dad's 84c10 and one on my brother in laws 85 monte carlo ss.
The easiest way right off is to pull each one off the front, ONLY the SMALL lines, one will cause the idle speed to raise and be sucking air, that is full vac. the other will not be sucking or change idle speed, that is timed/ported and where I would put my vac. for my dist.
Fire it up, open the hood and pulll off one line, if it has vac. hook it back up and then hook your dist. to the OTHER one. if the one you pull doesn't have vac. hook the dist. to it.
according to my pictures I got on here it's hooked to the ps.
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