I think I'm just gonna buy a junkyard GMPP... honestly in the beginning of this thread I didn't even wanna run a thicker front bar, instead just do poly bushings on the stockers. But eventually I learned that with this chassis the front really won't lose any grip even with a thicker front bar, since it leans so much... if anything it'll probably gain with less body roll thus both front tires keeping more contact with the road... I don't think the 33 mm vs 34 mm will make a difference to a point where I can actually feel it. I'll buy the GMPP now since it's ridiculously cheap and if for whatever reason I don't like the balance I'll switch to dorman or maybe even stock.
Not sure where you are located, but check the junkyard sway bar good before removing for any signs of rust. While this is a very good and cheap alternative to buying new this job is quite a pain for a novice. Most likely the cradle has to be dropped in the rear a few inches if you cant snake it in there, at least it did when I installed the Dorman on the Impala(should be the same). I've been wrenching for 30 years, and it isn't a fun job but totally doable for anyone with the time and tools. Then you get to repeat the process on your car.