i've got a 98 regal but im sure its the same button on the shifter, so my button stays in when the perf button/light is on, and sticks out a bit more when off.

i was stuck driving with out a cluster for a month and my knee hits the side of the sifter, so i looked real close to if it was on or off., and i can tell when it in performance mode or not just by how it shifts.