Is my 340 Overcarbed? Avg 5-6 MPG

Which spacer did you use? The 2" or a 1" open?

There's more sorting out to do, but, that's much better than the tune up that was in it before. A little elbow grease and minor changes can make a big difference in these things. There are some adjustments to do to clean things up a bit more.

Nice work and kudos for not giving up and putting in a great effort. :cheers: