Strange rubbing

I've got a 2nd gen AC prerunner that I've been running with a 2" lift (5100s set on the "0" notch with OME 886 coils) for a few years now and went up to 32" tires (Duratracks, I can't remember the exact size specs but I have TRD OR stock 16" rims) along with the suspension change.

Everything has seemed fine since I installed it all and had the alignment set (a little bit of rubbing at full lock, but I expected that and don't push the steering often), but I just noticed a patch on the pass side LCA (near the rear attach cambolt location) where it looks like there's been some significant rubbing at some point; I haven't had a chance to check it in really good light but it looks to have had the finish taken off of a patch maybe 2" wide by 1" high with enough surface rust that it probably isn't new.

Wondering if anyone else has seen something like this before.