Years ago, I had an 1986 Camaro IROC with 245/50R16 tires. It also wandered a over the road due to the tires (Eagle VR1). The dealer increased the toe-in, which helped but did not fix the problem. Is this the original tire size, I thought the SS came with 17" tires? My 93 Caprice pulled to the right when I first got it. Switching the front tires side to side fixed that problem. The Caprice does not wander at all, but has 225/70R15 tires. If possible, perhaps a narrower tire with a higher profile might help. Good luck with the SS, it’s a keeper.
Ed B.