Posting another followup in case anyone is experiencing the same problems as me.
Overall I've replaced the passenger side axle and hub, both control arms, put in a Dorman front anti-sway bar, replaced both trailing arms with Dorman's, and put in the GMPP rear anti-sway bar.
The rattle I may have pinned down as being a loose harness for a sensor, I'll edit this post in a bit after I test drive it. A washer fluid level sensor was hanging down, looks very similar to this:
The base is different (has that gasket to fit snug into the washer resivior), but the "level dongle" is the same.
Strange this was when I went to "remount" it, there was already a sensor in the correct place! I cross checked the part number's etc. on both, and they're both identical, and both plugged in... anyone have an idea as to why I have two washer fluid level sensors?...
And last thing, at this point the grinding noise has to either be tranny related (I'd bet on the differential), or it may actually be my A/C clutch bearing going and causing the A/C/ clutch to grind D: I knew it was going anyways, it "hooted" and whirred the few weeks it worked till the refrigerant worked its way out again, I'll do a quick test without the serpentine and see what happens...
/rant
