Hello I will help you with your question,
You are omn the right track with the security issue. Part of the security system is in the cluster so when you replace it the car thinks it is being stolen.
Try this procedure with the replacement cluster installed.
IPC REPLACEMENT When replacing the Instrument Panel Cluster (IPC) make sure the correct version is used, since the analog and digital IPC's are not interchangeable. Since the data contained in the IPC's microprocessors are vehicle specific, the IPC must be reprogrammed by a authorized service center when replaced. When obtaining a replacement IPC, all information requested by the authorized service center must be correct. This information ensures that the correct version of software is maintained in the vehicle. IMPORTANT: All replacement IPC's received from an authorized service center are configured, so that the IPC can learn (store to memory) the vehicle's ignition key pellet resistance (key code) value (PASS-Key II). The vehicle will not start until the key code value is learned by the IPC. The theft deterrent module re-learn procedure must be performed, refer to IPC Programming after replacement.IPC PROGRAMMING FOLLOWING REPLACEMENT To ensure that the IPC learns the vehicle's key code value perform the following theft deterrent module re-learn procedures.IMPORTANT: During this procedure the vehicles battery must maintain a minimum of 10.5 volts. If the battery is not fully charged or is weak a battery charger should be connected. NOTE, the battery charger must not be set to 12 volt boost. This prevents this procedure from working.
Where they say "cycle the key to run" turn the key to the start position and let it fall back to the run position.
Let me know if this works for you
You can do the relearn procedure the mileage will be incorrect but the IPC should learn the correct code. If this does not work you will have to find a shop that has a Tech 2 scantool and access to TIS.
Give it a try with the used cluster and it should work for you, if not I have other sources to get you going
Ok then you will have to find a shop with a TECH 2 scantool and they will be able to put it into learn mode
Does the replacement cluster light up?
I checked for AC Delco shops in Juneau but could not locate one but there should be someone with a TECH 2 there. If the replacement cluster lights up this will work.
You should see the spedo and odo so it sounds like you have another cluster that the illumination has failed. This is the failure mode for these clusters and I usually have to go through several used ones to find one that works.
All of the clusters have this same problem, there are several spedometer repair places on E-Bay that will try to repair your original or you can try car-part.com to try and find a working cluster but these digital clusters have a very high failure rate.
This is one source to have your cluster repaired, It is $250 so it is not inexpensive but you might be able to recoup that during the sale