Well it actually could need a change (and buell DID change it). Here are two pictures of ZTL1 :
And a picture of ZTL2
We can see that it goes a little lower on ZTL1 brake. About half an each lower. And ZTL2 brake line is straight while ztl1 brake line is a little twisted.
So I agree that both brake lines type might work on both caliper. But they have definitly not the same design.