1996 STS cel phone system, two way radios, onstar system

I have a 96 STS with a dealer-installed cel phone system that works through the read-out on the instrument panel and paddles on the steering wheel and has voice recognition.  It is analog and is no longer supported by cellular networks.  Also not OnStar.
Do you know of any replacement part(s)that will upgrade the system to digital or bluetooth, either of which would work through the controls as the original system did?
Thanks!

Answer
    I do not.  I would start with the dealer, then try an independent cellular vendor (one that does installations in cars) and then a radio installer.  Most of these guys, who used to do the two-way radios used by businesses before cellular and push-to-talk, also do complex cellular installations such as this.  Look in the yellow pages under radios--two-way.  I also have a feeling that, when you find out how much it is going to cost to upgrade, you will decide it's not worth it.  It's possible that the dealer could retrofit you into the OnStar system, ask them.  It's a good system with a lot of worthwhile features.
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