For the live diag you would need something like this plugged into the OBD (on board diagnostic) port of the car and into a USB port on a laptop. There is software that can provide pseudo real-time reports of various sensor outputs, one of which should be the charge temperature. I've not tried it specifically on the xfire but it *should* work.

I chose this pump because of several positive comments on this forum, and I didn't mind paying a little extra to make sure I was getting something that would fit. However they took ages to dispatch it, and then it didn't fit. The pump itself is the same but built for a smaller hose diameter. I had to replace the impeller housing with the one from my old pump. I think it's the same Mustang Cobra pump you can by elsewhere for a lot less money