Storing Race car for winter

I would like to avoid draining the radiator and block this year. As I see it I have 2 options:
1. Run an electric heater in the trailer.
2. put the car in the garage under the lift.

Heater: I have electric to the trailer and a small heater with a thermostat on it so it won't be running 24/7. I'm a little nervous about possible fire hazard.
Lift: Can only do this if I park something else underneath it. It's a 2 post lift that only goes up 6'2". I could take the wheels off, that might give enough clearance. It has been suggested though not to leave the suspension unsprung for long periods of time, has anyone else heard of this?

Drain the radiator and block: pain in the ***, but at least I could leave it in the trailer. Options are: try to remove all water or replace water with antifreeze.