Jeep prestolite distributor problems
The cam that operates the points doesn't look symmetric.
Crank the engine with the cap off watching the rotor, to see if it appears to wobble, which probably indicates a bent shaft.
Also watch to see if each of the corners on the hexagonal point-cam has to open the points a similar nearly identical amount.
Also if the #1 plug is shorted, the timing light may not strobe. So replace the plug or swap in one from another hole, and see what happens.
I know nothing about Buick V6s except that the very early 3800s ran like crap. By crap, I mean very rough.
The much later 3.8s are miles different engines. Smooth as silk,powerful,quiet, and my 2008 Allure/LaCrosse occasionally got 40 plus mpgs on the hiway. That was probably the single most reliable car I ever had; too bad it got written off by some texting-while-driving ................. person.
