Last night I pulled the gromet out that the vacuum line for the hvac unit runs through. When I pulled it out there was nothing attached to the other end. How do I go about reattaching this line and is it possible to run another line if it is too difficult to reattach the factory line. I have searched other posts but I haven't found anything in detail. By the way, the truck is a 2001 Lightning. Any help will be appreciated.