Has the motor jumped timing?

Jadaharabi said

A couple of questions on timing and carburation.
1986, 1/2 ton, /6, automatic Truck stopped running had no spark we eliminated the computer and set up a GM module with the ecoil. Reset the plug gap to 45. The motor will not run unless the timing is set to 20-24 degrees btdc. Even then it has a miss.
When I set the idle to where it would start and run it wants to run at 1500 RPM or more. And then the next time I start it it wants to idle at about 800. The carburetor is junk I would like to replace it with a non-smog carburetor. What are thoughts on that.

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The timing problem could be as simple as the outer ring on the damper has slipped and the timing mark is not at TDC, so agree that needs to be checked.
It is also possible that the two wires going to the distributor are paired incorrectly. Try swapping those two and see if the motor runs better.
As part of the HEI upgrade did you remove the lean burn distributor and install an electronic Mopar slant six distributor with a vacuum advance can? The lean burn distributor has locked ignition timing.
Lastly, if the carb on the motor has wires going to it from the OE Lean Burn set up. That carb will never work right with the Lean Burn removed. You need a non Lean Burn carb.