I am not sure about the Trans won't take it line, as to why they did not make a Stage 2 for the PT, as if you have a '05 or newer and add Stage 1, you are actuatly are getting the So called Stage 2 power levels. For '05 and up you upgrade to 235hp 275 ft-lbs torque measured at the Wheels.
The original Stage kits up to and including '04 were measured at the crank, you have 10 to 15% loss with a 5 speed manual trans and 20% with the auto trans.
The original specs in the '04 Mopar manual are:
Stage 1 235 hp 240ft-lbs
Stage 2 260 hp 280 ft-lbs
Stage 2 with toys (SRT4 only) 265 hp 280 ft-lbs
Stage 2 (High Octane Mode) 280 hp 300 ft-lbs
Stage 3R (SRT4 only) 310 hp 325 ft-lbs
Stage 3R (SRT4 only Hi Octane Mode) 355 hp 365 ft-lbs
With the '05 and up measured at the wheels at least 5 of us over on PT Crew have dyno'd our cars, (mine just this past Saturday) and we all made 235 +/-5 whp 290 to 305 ft-lbs torque to the wheels, now if you add back in the trans losses 20% for the auto you have 282 hp at the crank, 360 ft lbs at the crank.
So for the '05 and newer with Stage 1 and a free flow exhaust and take the restrictions out of the stock air box and intake tube you are past the original PT and SRT4 Stage 2 specs.
Now I will not go any higher until I have my auto trans upgraded for more power.