My C3 is a 2001 and has the DBW like your 02 Tahoe. Only the 00-02 TAC, TB and PCM will work together.
The pedal is the same 00-05. 2006+ will work, but the plug on the pedal is different.
It is an absolute nightmare to find DBW parts for the 00-02 trucks that had it. Any place that says they have the TB in stock will send you a 2003 DBW TB or a cable one. You will probably have the same problem with the TAC. The TB on my C3 was damaged when I got it. I'm running my C3 on a 2003 PCM with 03 TAC and TB now. I finally found a 2001 TB, so I will be switching it back shortly now that I have all the pieces.
Not sure what you are putting your engine in, but I would consider converting it to DBC.