Think I would look at the wiring to be sure you don't have wires that are corroded. There was an issue with Dakotas from the early 90s around the brake booster area where wires broke off a bundle. Or it could be time for a new fuel filter.

The biggest issue I ever had from my carbed 3.9 was the feedback carb, and a bad fuel filter. I replaced the filter, found a different carb to replace the original (that had been rebuilt several times), and the problem went away. Gene