When I removed my plennum this past summer, I found that I had to cut the majority of the water lines away from the metal pipes under the plennum. Before i removed the plennum, I notice that my anti-freeze was turning orange from rust somewhere in the cooling lines. Once I removed the plennum I found that it was coming from the rusty pipes which or located directly under the plennem. If you bypass the these metal pipes, you will avoid future rust build up. You will also avoid the cost of replacing all those little section of hose specially fitted for the Z. I bought one long piece of steel braided hose (Looks Aggressive) from Ram Chargers for 25 dollars and cut it to size for the bypass. You could use a regular water line from murray's auto parts which would cost about 12 dollars.
