Once you have found your classic car or truck project, the transmission may be damaged if you start the engine, or tow with rear wheel turning and the drive shaft in place. Many of the transmissions I take in have this type of damage. Spun bushings, destroyed pumps, score shafts. This damage will drive up the rebuild hard parts costs. If you plan to tow with rear wheel turning, then pull the drive shaft to protect the transmission. If you are attempting to start the engine that has not run for a long period, then protect the transmission by ensuring the trans has oil in the sump or contact me for how to disconnect the trans from the engine to protect the transmission.
A note about cold weather storage. All cold metal will condensate water during temperature fluctuations, and that process occurs inside the transmission. If you are going to do brief cold weather starting of your vehicle, be sure to allow it to run long enough to get the transmission hot. Short start, run and shut off procedures may mix condensate with oil and distribute the water inside the valve body, pump, and other critical parts. If allowed to remain, rusting of parts will occur.