Hi Jeepenstevo,
I am going to take a different approach to your carb problem.
Your starting post, reduced to the essence, has two clues: (1) "running way to rich" and (2) "it is really sucking down the gas." Clues (1) and (2) are really different ways of expressing the same phenomenon.
The fact that your Jeep is "really sucking down the gas" suggests the carb is malfunctioning at speeds above idle. Unless your Jeep operates all of its running time at idle, mis-adjusted idle mixture screws (within reason) won't make a huge difference in gas mileage. Given also that your BBD has (or did have) idle mixture screw limiters, the idle mixture screws can't be far off the proper setting.
My guess is that your Jeep/carb has problems other than idle mixture screw adjustment. Unfortunately, the possibilities are many. Too many to attempt a long-distance diagnosis without further information.
This is not to contradict the preceding posts, it is to play the odds from a different starting point or perspective. Given that your Jeep has the Carter BBD, with stepper motor adjusted jets, and the associated very complex and failure-prone emissions control systems, my bet is that the fault lies there and not with the idle mixture adjustment.
If it were my Jeep, I would begin the diagnosis by first confirming proper operation of the automatic choke and the computer controlled carb metering needles.
Regards,
Gadget
