Trailering to a race in freezing temperatures

I put a petcock in both drain plugs in the engine block. Then I use a 36 inch 3/8 extension to reach down between the header tubes to push on the wings and spin them open and closed. A long with the one in the bottom of the radiator gets enough water out that I have never had a problem with the little bit of water that's left since the mid 1980's. Now I will say that my garage is not heated , but it is attached to the house with a room over it so it does get some radiant heat form the house. This morning it was below 0* outside and the garage is 35*, cold but nothing freezing. Hope this helps for your decision on which way to go.