My next project, and I am really looking forward to it, presents a problem. The bike, a 1971 Bianchi high end machine, sports two holes in the top tube that the original owner drilled to allow for an internal brake cable routing. Needless to say, I want to repair the holes, as in plug them up and do so without damaging the lovely chrome plated integral Bianchi head set shell. I am seeking suggestions as to how to do this. The two most likely options are JB Weld (not what I really want to do) or silver solder an alloy plug into place using a small soldering iron and taking great care to NOT damage the chrome. Any suggestions would be appreciated. Thanks...