TT NIUM

First, thanks to Quicksilva, Raven, Jenner for guidance in my attempts at adding a sub. Unfortunately, in the process of wiring I managed to short out the left channel of the speaker outs that I decided to use to feed a Basslink. I put a lot of effort in doing a good job routing the wires, but my problem was trying to use 3/16" female disconnects to tap into the outputs. They really need 1/8" (.110 actually) disconnects. The 3/16" apparently touched while I was testing the speaker level. I later obtained the .110 disconnects and replaced the 3/16", but then found out the left channel was out. I don't suppose the dealer will fix this, since obviously it was due to my tampering. So now my options are:
a) to use just the right channel to drive the sub (will the unbalanced load eventually blow the right channel?)
b) tap the rear speakers after the Bose amp (I had real difficulty trying to remove the back panels, which is why I avoided this option to begin with)
c) tap the preamp outs (I'm not crazy about messing with low level outs, especially since these wires aren't shielded. Don't want to introduce noise into the system.
Any opinions?