I've got a nice OBD-II scan program that uses a laptop and custom cable (from OBD-2.com) that costs ~130 bucks and allows you to connect, view live sensor info, check & clear trouble codes, and datalog vehicle data during a test drive....I know that obd-I and II are like night & day, but is there anything similar to that for OBD-I that is relatively inexpensive??? The GM service manual refers to a "tech-1" device that seems to do this....Anything aftermarket???