Winterizing Wilbur

Winter is here and I decided to put a water heater by-pass kit on the old Winnebago. This weekend is a Boy Scout campout and the temp is planned to be well below freezing. The kit looked like an easy fix and at $18.95 it was within budget. My heater is under one of the dinette seats. The only problem was not a bunch of room to turn wrenches inside the seat area. Last year I got the drain plug out of the water heater for the first time. Now I need to blow out the lines and pump some anti-freeze into them.