I was told by a few venders that you can go 12" without replacing any lines, just need the namz
I just measured my la choppers prime apes, they're 16" exactly from center of the lower bar to center of the upper bar and I just bolted my controls in place with the factory brake and clutch lines attached. So factory lines WILL work with 16's. Keep in mind tho when I did the Vindikta 12's I ran my master cylinders through my triple trees and back into place in a different orientation to free up some line, but still didn't have to open up either system.
Just hang in there, E.P. is a top notch vendor. I bet they had trouble getting ahold of Brett (KST) he is very slow to return calls. I talked with him a few times on facebook and sometimes it takes a few days. I guess he is busy making bars.