Hydraulic Hose Length...

[oldguy00]

Sorry, another hydro question (while I still try to figure out how I'm gonna get it through the damn bars).....

Once you have the lines routed through the frame, attached to the calipers, calipers attached to frame, etc, and you are at the point where you are ready to attach the brake levers and connect the hydro hose........how do you best determine the exact length? Do you try to cut it so that it maybe would go like 1-2cm past its connection point on the lever, and hope that you'll be able to push that little bit extra back through the stem/frame after you get it hooked up? Though the lines feel so stiff that I'm not sure I'd be able to push any back in....
Thx!