If you decide to go with a different alternator, be sure that it's compatible with the computer as it controls the alternator output. Either that or it has a very smart voltage regulator. Not sure which.

 

I did a stereo for a friend of mine, and we upgraded his alternator to a 400amp alternator. We found the alternator on ebay, and I just did a quick search, and the company is still around, and happens to have 07 tahoe alternators. Here's the link.

http://cgi.ebay.com/ebaymotors/05-07...mZ130205402460