Here you go:
I did this a couple of years ago now and ideally you need to do a couple of mods to get a decent functioning headlight, firstly remove the self levelling motor and replace it with your manual levelling motor but you will notice that the "ball" on the end of the manual motor is slightly smaller than the auto levelling ones ( I inishally found the lights seem to jump a little ) I cured this by putting some heat shrink over the ball and this gave it a nice tight fit, then cut the plug for the auto levellers off, then using the plug off your original manual levellers do a bit of soldering, I will list them as old and new, old being your original wiring on your manual levelling motors and new being the S4 wires.
Connect the old blue to the new black
Connect the old brown to the new blue
Connect the old black to the new brown
You will also need to change the sidelight bulb holders if you want to use your original 501 sidelights, you should then have fully functioning headlights with manual levelling via the original switch, I've never had a problem with mot's but loads will say it's not legal but I can't be ***** with that argument I just wanted to be able to adjust the headlights if needed,hope this helps you.