I suggest learning how to tune yourself. Much good info on the web. Pcm section has a tuning tutorial in the sticky threads. Also
LT1 PCM Tuning - Welcome! has some good tuning info.
Then get the tunercat obd1 tuner. With it you can change any and all info in your 94 pcm, including changing the vin number stored in the pcm, in case you ever buy a new or used pcm. Tunercat obd1 tuner is available at
TunerCat.
You will need a special cable to hook car's dlc to your laptop's usb port. You can get those at the tunercat site or
ALDL OBD1 OBD cable OBDI OBD2 engine codes
Tunercat makes a deluxe package that includes tunercat obd1 tuner, $EE definition file you'll need to read your 94 pcm, cable, and the DataMaster scan program. All for around $250 DataMaster is a great obd1 scan program that not only reads codes and scans real time sensor data, but also logs it to a data file that you can playback on DataMaster. You can also post up the data files for members here to assist you with understanding the readings.