It sounds complex but really takes longer to explain it than to do it.
Mark, you hook the Tech-2 up to the truck and go into SPS and it downloads the truck configuration to the Tech-2. Then you turn off the Tech-2, disconnect it and take it into the house and connect to the PC. Then you fire up TDS and turn on the Tech-2 when it tells you to and go from there. At the end of the download process from the PC to the Tech-2, you'll again shut off the Tech-2 and take it out to the truck and as soon as you power it on it automatically starts programming the modules.
Here's a good visual tutorial. He's using TIS2000 but TDS is similar.