I just finished my X77, when I smelled some oil. Discovered the oil gauge line right at the gauge managed to dump 2 quarts under the carpet. It is a plastic line. I ordered a new one from OPG and I bet it is plastic. Is the original plastic, or copper , or something? my 72 P/U has a metal line. If it is plastic, what is the correct installation procedure to keep from screwing up the new one?