'04 Bonneville, SE 3.8L.
Recently changed the heater/fan control panel with another - easier to change the entire panel with a used one than to change the individual lamps in it - the temperature control seems to be very touchy with the AC. The last 'notch' CCW results in a large temperature change. Is this normal? Didn't notice it prior to changing but it could have been the same. Is some kind of a recalibration necessary when the entire control panel is changed?

The blower motor is quite noisy again, changed out twice with aftermarket units. Has anyone had any good fortune with any aftermarket blower fan? I am believing I'll have to get an OEM to correct this problem. The noise is a low pitched rumble, sounds like bearings (or lack thereof). Seems the aftermarkets are only good for 25k miles or so. The car hs 182k on it and still runs strong.

Let'* reword this:
I changed the HVAC control panel, which is below the radio, with a used one.
Is there a recalibration procedure necessary for the Instrument Panel Module to ensure the motors for the doors in the air distribution system are fully opening in the max cool position? Or is there nothing in the HVAC control module that would effect this?
I do not have access to a scan tool that can read specific attributes within the vehicle, or that can reset/force a parameter. I may be able to borrow one but I myself do not have one beyond a simple OBD-II reader.

The blower motor is a thorn in my side. Does anyone have a recommendation for any aftermarket unit? One that they have found that actually lasts for over a year?

There is no re-calibration process.

I bought my HVAC blower from Rockauto.com and have had no problems for 3 years.

Rockauto offers several different manufacturers of blower motors. Do you know which one you bought that has lasted this long?

AC Delco. That is the OEM manufacturer.

Apparently that'* my problem, I bought an aftermarket that didn't last. Sometimes there are big differences between OEM and AM parts.