I've been reliving my junior high days when I was really into Chicago. Didn't pay any attention to Terry's guitars back then. Here are the guitars that I have been able to find photos of him playing. Please comment if you know any more about them such as year, or if you were able to see him play.
Fender Stratocaster
Gibson SG Standard pre 66 model with a small p/g (p/g is removed)
Gibson SG Custom post 66 model with a large p/g
Gibson Les Paul Professional
Gibson Firebird reverse body (can't see the pus to tell if it's a I or a III)
Fender Telecaster with Strat bridge, maple board with Gibson HB pu in the neck position aka the Pignose guitar
Anybody seen on the documentary his daughter did "The Terry Kath Experience"?
Fender Stratocaster
Gibson SG Standard pre 66 model with a small p/g (p/g is removed)
Gibson SG Custom post 66 model with a large p/g
Gibson Les Paul Professional
Gibson Firebird reverse body (can't see the pus to tell if it's a I or a III)
Fender Telecaster with Strat bridge, maple board with Gibson HB pu in the neck position aka the Pignose guitar
Anybody seen on the documentary his daughter did "The Terry Kath Experience"?