The original setup on a 2003 is this. Your HVAC controller sends a serial signal to the PCM requesting AC clutch ON. If the PCM criteria are met, it will engage the clutch and compensate the idle based on tables it has stored for the TQ necessary to run the AC compressor.
None of which is really necessary. The PCM will automatically adjust the idle to make up for any extra load, no matter what it is from AC compressor or no.
Your original 95 system didn't run the AC request through the PCM and you won't need to on this one either.
The 2003 system is set up that way so the PCM can kick out the AC clutch at certain TPS % , you can't use this feature anyway since you won't have a serial based HVAC control unit.
If you had a 99-02 PCM you can make it work this way, because they didn' t use a serial based system. They used the same basic setup as your 95, but it did run through the PCM.

Really not worth worrying about. Just set it up like the 95 factory stuff was and it will work fine.