I have installed a titan tank on an 04 LB7, after install was complete I went to top off the tank, what a JOKE! So in order to make things right I am trying to think like an engineer and fix it. I dont see any reason why I couldnt order an LLY filler neck and just leave the tank vents tied together then tee'd up to the top of the filler neck. I am hoping that someone has also been down this road before and I am looking to fix it quick as this truck if for a customer and it looks like I am footing the bill to make things right to my customer. An LLY filler neck is around 240 and a week out.