10 gal corny keg liquid post troubles - anatomy help

[eelgerg]

I bought two 10 gal corny kegs and was ready to fill them this weekend when I realized that they had the dip tubes removed. One had the posts removed too. The dip tubes seem to connect using a tail piece on the inside of the keg, but this is where my confusion starts. I can't seem to be able to get the liquid post and dip tube system to work properly, and am also uncertain about how the liquid post is installed on these kegs as there seems to be more parts than on a 5 gal keg.

Issues:

- how does the dip tube seat on the tail piece in the inside of the keg? Mine seems to swing loosely - ur there is nothing putting pressure on the inside o-ring and dip tube

- overall length seems too long. Dip tube is really had to install due to no clearance. Should I fix this by maybe cutting 1/2" off the end of the dip tube?

- external ball lock fittings. These corny kegs appear to have one more piece (3 piece fitting) compared to my 5-gal corny kegs which are just two-piece (one inside and one outside threaded together.

Can anyone help me to figure out how to correctly put together this corny key's liquid post fittings?
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