Cool, my kind of boat! Wish I could help with your cable issue, but I've never dealt with one that has the cables running down the same side. I look forward to seeing it all painted back up.
I was about to post the link, but kfa beat me to it. Post #16 in his forum link has a good diagram for cable/drum steering on one side. I would suggest going to Lowes or Home Depot and buy some new cable. It's cheap and a lot easier to change out now rather than later. Your set-up is a little trickier because the drum fits in the housing. Good luck.