Using vacuum gauge to tune engine?

Moparofficial
I recently after fussing with it a little more got it to about 12-13deg in Hg. But I haven’t right now been able to get it below 1000rpm without it running rough. When I adjust the rpm’s up to @1000m it smooths out. But now that AJ/Forms has chimed in I’m rethinking what I have done. I think I may have more to do?