This is kind of a nifty thing I found. Not really of any immediate use but it provides the service bullitens available to a quality shop on how to reprogram your PCM. You can use it to see if a problem you're having is a common one. All it takes is your VIN. Check it out: http://calid.gm.com/vci/
. Example for a '95 SE:
Part Number Cal. ID # CVN Bulletin # Description
16266454 16266346 N/A N/A control module calibration
09351504 09351412 N/A N/A new calibration to reduce the potential for intake manifold overpressurization
09353154 09352766 N/A N/A allows for crank angle relearn and vss malf code to set.
09357194 09357035 N/A 776530 corrects pre-ignition which causes eroded spark plugs bulletin number 776530
09361364 09361300 N/A 876514 calibration to correct potential acceleration or deceleration stall. bulletin number 876514
09379854 09379800 N/A N/A includes driveability improvements, fix for dtc p0405, and fix for transmission rolling stop re-acceleration shutter
Check it out and see if its time to have your PCM programmed.