You mean the line from the brake res? As long as the e34 one is long enough, you will be fine, it's just a rubber hose. If you are talking about the hard line from the clutch master to the slave, it might work if you bend it appropriately.
Wide Open Throttle Technologies (WOT-Tech)
The 1986 325es Delphin project LINK
Project 1988 325i sedan "Pinky" LINK