Speaking from W126 experience, to do a full conversion, you would need to run vacuum lines and get the euro headlight-switch assembly which provides a thumbwheel that modulates vacuum to raise/lower the beams.
No need to do all that if you don't need want that feature, as they will default to the lowest angle and you can simply aim your headlights to the desired fixed-height.
They may require a different power connector for even the most basic installation--check with Phil on part numbers. Cheers, Andrew Seidel.
85 500SEC Lorinser
83 300D Turbo