A lot of late model cars use a plastic-like fuel line, in certain sections, but never the entire length of the car. I'm surprised you haven't had some kind of problems already. I would definitely NOT keep it.....just too scary for me. It could be damaged from heat, a minor "bump" in cold weather...heck, even a rock or other foreign object thrown up could puncture it.
Replacing the fuel line with the body on the frame ain't an easy job....in may, in fact, be dang near impossible, if you plan to run it the way it was originally. Cutting/splicing in a new steel line isn't a good idea, either, since the splices can leak.
I saw a guy one time get a loooong roll of 5/16" fuel line, and run it thru the front, to the rear, a little at a time, all the while bending/tweaking it to get it thru all of the obstacles along the way. Of course, it looked nothing like factory, but it was one piece....it got the job done, with some aggravation thrown in just for grins.
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Joel Adams
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