Bought a used trailer that was originally from Tractor Supply co. Its a 5x10. It has these tube welded so that you can feed the wires through it to go to the back of the brakes. I cant get the wires to go through the tubes. Tried coat hangers and a long piece of rebar that i cut on the end to look like a drill and tried to drill through it and also tried hitting in through. It seems to get stuck about 2 feet in and wont go anyfurther, just like its hitting metal or something. Any ideas?