If this is in the wrong spot please move it but I was not sure where to post this.

I have a 97 GTP that is/was stock and I thought that my PCM had died based on several things. So I got a different one that turns out not to have been originally from a 97 GTP but when I run the numbers off the PCM it says it was from a 97 Olds Cutlass. THe PCM had been tuned with the following changes

3-1 and 4-2 skip shifts
- Transmission line pressure increased
- Shift points moved (5800-6000rpms)
- Fan turn on points altered:
- Torque abuse modes are modified to eliminate bog at launch
- Trans shifts are quicker
- 185 degree turn on
- 2 minute fan on at key-off\
- MAF calibration adjusted for proper operation and yea
- Removed “40MPH WOT lag”

The PCM installed in my GTP fine and actually started my car right up and after running for maybe 10-15 minutes or so it smoothed out and I began to drive it. The car ran like a beast (in a good way) and had never felt stronger or faster although I did not run it past about 75mph with the "new" PCM. It shifted very differently than the stock PCM and actually threw a code P0748 which is a pressure control solenoid. I am not one to ignore codes and stuff so I decided to put my old stock PCM back in the car to see if it would work. It did. The P0748 is a history code but not currently a DTC with the original PCM in place.

My question is two fold. Is there a reason not to use the PCM that says it is from an Olds Cutlass myself? I really liked how the car ran and the fan cut-in but don't want to damage the trans. Is it just tossing that code cuz the stock solenoid is basically saying "hey why am I not working like I am supposed to"? or is this a potential BOOM? Also if I can't/should'nt use it I would want to sell it but I don't want to sell it to somebody without disclosing the issues first.

Sorry for the novel but I hope this makes sense. Thanks!