Happy Holidays!
Urgh, mechanical will always be challenging with these frames that are meant to be used with electronic. I would still try to have 2 lines on each side of the stearer - similar to my picture but just 2 lines on each side instead of one each. That way you should have a bit more space for each line. Have not installed mechanical on this, so no hands-on experience, just throwing out some ideas. I think Serge hast some experience with it.