340 tunnel ram issue

Back to basics. Break it down. It ran good when you got it. It started running bad when?
Did you get a back fire on a shift and then it started running bad? Did it run great one day and the next day nadda? Did you swallow a bird or small child at 7 grand?
You have Holley carbs, it could be something as simple as a blown power valve or a vacuum leak. What type of ignition system? Bad points? Bad ballast resistor? The tune up problem you're having doesn't really care if you have a two barrel carb or eight strombergs on bathroom plumbing. Just relax and work through the basics. You'll be glad you did.