Tires wearing on the inside due to toe means she's running duck footed and needs toe in. If worn on the outside then to much toe in and needs let out. Due to the wishbone rear suspension in our cars alignment is just as critical as the front. When I first got my SC I couldn't keep a rear set of tires on it and she was quite squirrelly. It took 2 tries to get it to stop that and we over adjusted toe in to compensate for worn suspension. Kept setting it then drive down the road then put it back on the machine till it would stay where needed. Even had to bend old toe arms to help in adjustment. Since then I rebushed control arms with poly bushings and tires wear ok. I plan to put adjustable aftermarket Lca's, toe arms and links on it with new aftermarket uppers from Toyolex (NAS) so rear can be fine tuned easily. This is a commen problem with these old girls once they get a lot of miles on them and need rebuilt. Good luck with your problem and hope you get it fixed as tires are expensive.