Chuck, If I'm not mistaken, all Chrysler Torqueflite 3 spd transmissions in the late 50's, 60's, and into the 70's had a "Kick Down Rod" connected to the carb linkage and the tranny. When adjusted correctly it would down shift the trans into 2nd gear, and even into 1st if the speed was low enough. All it took was moving the linkage far enough to engage the kick down rod that was set at a pre-determined spot on the carb linkage.
I'm not sure when Chrysler switched over to an electrical switch to activate its passing gear.

I assumed the Limited Crossfire Automatics had the button too, but it seemed like it was only mentioned when talking about SRT's and their "Warp" button.
I guess I was mostly wondering if any Limited XF owners had affectionately bestowed upon their own personal automatic button some sort of name.
But nobody has responded to that part of the question.

To answer Mrphotomans question. According to what most automotive magazines report from their road test of both cars, on average a SRT6 is approximately 1.5 sec's faster than a NA 6spd XF in the 1/4 mile, and nearly 2 sec's faster than an automatic. Of course these #'s are for 'Box Stock" cars. (We all know how fast SRT's with mods can be).