This really has my stumped. When accelerating lightly sometimes it feels like the car is bogging and just doesn't want to move and then other times feels just fine. Trans seems to shift excessively under light acceleration also

Almost like a feeling of something temporarily applying the brakes and then releasing. So odd.

Just looking for some general insight on the issue.

In the future, please clearly specify WHICH car. Some will assume you posted in the wrong section if they don't know about the other one. All two-car owners should do this as a rule.

Full tuneup done yet?

I was told that the plugs, wires, lim gaskets, uim, trans flushed, and filters were done about 25k ago. But since I didn't do/witness it, thats all I know.

Thank you for editing your topic title.

Time to check all of it. PCV, fuel filter, O2, air filter, plugs, wires, coil posts, check the coil resistances per Techinfo, remove and clean the TB/MAF per techinfo for cleaning, and check for vacuum leaks.

Typical stuff for a newly purchased Bonneville.

wouldn't hurt to redo your battery connections (both ends) and check your ground bus connections

did u get another car?