Yesterday afternoon, the work was completed on the truck. I have a brand new transmission, a new starter, and a new water pump. It seems to be running rather well, but I think the water pump might not have been the only thing causing the over-heating, as last night it boiled off some coolant yet again. It doesn't appear to be as near as bad as it was before, though. It's possible that they just over-filled it. I still suspect there's a thermostat/sensor problem somewhere, but at the moment, I'm so tired of sitting it's not something I want to put it back in the shop to rectify. It's something I can have looked later.
In other truck news, I signed the papers yesterday to begin the lease/rental agreement, so all of the financial responsibility for the truck has now shifted to me. With all of the work done on it this past week, I'm rather confident that I've got a fairly decent truck. I know things are still going to fail, as it is a used and aging truck, but with what seems to be a solid motor and a brand new transmission, the things which fail in the future should be relatively minor.