Piggyback.jpg

I got an IBS for my 2014 Outback V and a kit to install it from Wakemakers. I'm not sure I got the right kit though. The top right is the bag vent line that goes to the ski locker vent. Top left is a T that goes the the through hull fitting then continues to the IBS fill port. So far so good but the middle connection in the picture has a T in it that connect to the IBS fill but where does the other part of the T go? Shouldn't I just have to run the existing bag vent line from the ski locker that went to the through hull fitting, connect it to the IBS fill port and then run the vent line from the IBS to the through hull fitting? I think I can use what I have and make it work but where would I want to put the check valves (or what I think are check valves?) Pictures of check valves below

Thanks

Karl

checkvalves.jpg