2019 ram 6.7 HD 5500 aux fuel line tie in

[Markzed011]

Hey all, I have a 2019 Ram 5500 service truck with 6.7 cummins that I want to install a diesel heater for the tool cabinets. I have read about the auxiliary fuel port.... I am not quite sure but I think I have it on my fuel sender.... however its really hard to access as I have a full service body over the chassis and tank with poor access... Ideally I would be able to lower the tank and connect but I am out on shift working and dont have the time to do that between jobs... so I am looking to see if there is another way I can tee into lines to pull fuel for espar/webasto style heater?
Also tank was just filled up too lol

Any thoughts or suggestions would be helpful too!
Thanks!