still uses alot of GAS

OK I changed my vacuum advanced and thought that would take care of my truck drinking alot of gas so it did help a little but im still burning very rich and drinking alot of gas. Can anyone tell me what else might be causing me to be burning rich still, I have a brand new 32/36 Weber, new beldin wires,new NGK plugs,rotor button,distributor cap, PVC valve etc etc so now Im lost about ready to sell the truck which I really dont want to do. Iv spent alot of time and money into my truck but cant hook my lawn care trailer to it cause then it drinks even more,I know pulling my trailer causes the truck to use gas but not when Im running with no trailer no weight at all in the back.Its still burning super rich so does anyone have a clue.

If you have mechanical lifters you might need to adjust them. To maximize lift they need to be adjusted to .008 at the lobe interface and don't even fool with trying to adjust them to .012 at the end of the rocker.

Do a compression test, before and after adjusting the valves. and a leak down test. Maybe the motor is worn out. If you are showing 100-120psi the motor is trash and needs new rings.

Maybe the coil is bad. (Not enough fire to light off the mixture well)

5 Speed or Automatic?

Gas leak at or around fuel tank? They are known to rust and leak, particularly at the seam around the middle of the tank.

Brakes fully releasing? Are you able to push it freely in the driveway?

You checked vacuum advance but did you check the centrifugal advance? I have a B2600i where the centrifugal advance wasn't working.... wouldn't budge more that 1 degree at high rpm. Needless to say, the engine would get weaker the higher the rpm due to insufficient advance.

Choke disengaging properly?

Float set right? Carb tuned right?

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Jim, you ask for ideas and then you shoot them down. Do that often enough and people will stop offering ideas. Do a compression test. That will at least rule out low compression. Worn out motors don't always smoke. A weak coil doesn't light off the mixture. I recall having this discussion with you already. A float not set to the right height can make the truck run rich. So can a choke not opening up all the way. What is your ignition timing set to; Centrifugal should add 15 to base timing of 6 and vacuum advance should add another 20 to a total of about 40. Maybe the weights are stuck inside the distributor. If you aren't willing to do detective work don't ask for ideas from those who do.