Today I fixed the broken rear window defroster tabs on my Xfire. I opened the back of the top to where it was sticking straight up so I had an easy view of the tabs. I laid some towels down on the top cover in case something fell so it wouldn't get scratched. Then, I flattened the tabs and hooked them under the metal brackets that are spot welded to the electric window grid on both sides; then I soldered them. I tried to place the tabs in a direction where they wouldn't be flexed too much by putting the top up and down. They seem very sturdy...but time will tell. I'm not sure if they broke with flexing from putting the top up and down, or if they were broke off when the window tint was put on with the previous owner. They have been broke since I bought the car.

After it was done I ran a VOM across the terminals and was getting 12V, so it appears to be working.

Pics attached.