[dsraven]

if the line runs inside the frame rail you can bend up a U shaped piece of metal that fits over the frame rail, with a small lip to the U shape keep it from moving around. then use some large gear clamps around the whole thing to keep it in place. if you wanna get real fancy then cut a couple of slots where the gear clamps go. make it longer than required. this way it is easily removed if you need to or find it didn't work or needs to be bigger. you can cover it with an insulated wrap if you want to but it shouldn't need it. if you have a used appliance place nearby or a graveyard for used appliances then you could come up with a piece of painted light aluminum from a dishwasher door that would be easily bent over the edge of your workbench. use a split piece of fuel line or other insulator on the edge of your frame rail before installing the tin work and it won't rattle when done.