As noted, you will need to have the levers clamped on a non-tapered section of the bar; they will certainly walk down the taper and become loose as they are now.


You might try using a 45- or 90-degree brake noodle to turn the corner out of the lever, to avoid interference.


Also, I think you will find that the levers will not move as much as you are moving them when they are cabled up, and merely touching the other cable may not affect their performance.