Bring Sheila Home Acheivement not unlocking

For some reason, I brought the Tank from the beginning of the level into the Tower and it didn’t pop. I made sure to keep the tank back the whole time while killing enemies and then run back and move it forward. Did I miss something?

Did you park in in the building across the bridge?

Like hermit said, you need to cross the bridge at the end and drive right up to the door after flicking the switch for the bridge