Connecting to water pump for winterizing

After taking a week in Lancaster where the temps have dropped, we need to winterize our TT and our local dealer is 10 days out and cannot help so we are attempting to do it ourselves. We have emptied the water heater, all drains and positioned the valves for bypass. Now we are at the point to connect the hose to the water pump and draw from the antifreeze containers. We thought the proper line was the line in white in the right of the picture, but when we turned on the water pump it start blowing back into the jug so it must be wrong. The is another connection on the left (black) that could be the right one but we are not sure and it is really hard to get to. Can any one help us? hopefully the picture comes up. We have a 2013 Freedom Express RLS.





Update...2 hours later....we figured it out.. had the wrong end of the pump...All is well. Always something to learn.....