[QueWhy]

Removing the antenna is quick and easy. You don’t actually need to remove it, just get it out of the way.

One nut on the bottom L bracket. Unscrew the cap on the top of the antenna, (outside the car)and the whole thiing will be free.

Edit: what do you mean by the thermostat being frozen in place? There shouldn’t be anything connecting it to the car, just the oil lines.