Auxiliary in bed fuel tank question

I installed a Transfer flow 50 gallon and the kit came with a T with a built in nipple to attach the hose from the aux tank for filling the main tank. I had to take off short vent hose, cut it, install the tee and clamp back on the main tank. Then I had to slide the hose from aux tank back on and clamp it as well. I know its not the same, but this is what the kit had. Pretty simple.
Cut and past and look at page 10 of the instructions.
http://www.transferflow.com/content/pdf/inst836.pdf