I just used an anti freeze hand pump this year. Connect to city water connection and open one valve at a time inside and pump until the anti freeze is flowing through. Then dumped anti freeze in all of the traps and tanks. Took 3 gallons of anti freeze. Will install the winterizing kit for next year.
The way the 25v is setup, you are actually pushing it through the pump on the city side. You could actually switch over to tank fill and pump into the fresh water tank and cycle through the pump that way too. Of course you want to bypass the hot water heater when you pump the antifreeze in or you will just fill the hot water heater.