1. When the rear springs are moved inboard does it adversely affect handling? On the street,no, cuz I put bigger tires on,lol
2. Does relocating the springs buy you any tire width without mini-tubs? Yes,the springs and the inner tubs pretty much line up to a plumb-line. You can move the sidewall over until it hits the inner side of the tub, pound out all the areas that need clearancing, then push the sidewalls out far enough so they don't rub; which varies by your driving style, type of bushings,shackle length,and ride-height. I lowered my car and run 325/50-15s @1/4 clearance in straightline work with modest cornering. And with 295/50-15 at about 1/2" and anything goes.
3. If moving the springs inboard causes excessive body roll, could a fat sway bar control that? I can not perceive any difference.
Be careful with a rear sway bar, it can get you into a world of trouble... if you don't have a matching front.
