I installed a winterizing kit on my pump this past weekend. It took less than 5 minutes and required no tools, except for a screwdriver to remove the access cover.
Remember, this is on the suction side of the pump. Just hand tighten and be on your way.
Me, I blew the lines with compressed air first. This cleared 99% of the water. In doing so, I cleared:
Water heater (blew air with bypass on and off)
Black tank flush
After all that, I bought a 5 gallon water jug just for winterizing. I fill it with RV antifreeze and turn the pump on. This makes it easy so I'm not swapping gallon jugs.
Flush away. Dump extra down traps.