Fuel (??) lines inside the cab B-pillars?

[XXL]

On the new cab I'm working on there are hard lines poking out of either side of the cab, just behind the door jam and just below the rear glass... I've taken many a seat tank out in my days and never ran across these before. I ASSume they are some kind of fuel lines. So, on to the question...

How on earth do you get them out? They seem to be permanently affixed between the inner and outer sheet metal of the cab.

Any ideas?

Kenneth