Having just completed my 155 rebuild the only outstanding problem was the inability to adjust the headlights since the all the adjusting pauls were either seized or immoveable. Whilst it may seem desperate I removed the adjusters and plastic clip, opened an access area in the front cross member where the vertical adjusters were obscured, freed off the vertical adjuster with WD40 and then cut a slot in the top of the cog. Using a wide screwdriver I can now adjust the headlights with ease. This after spending far too much buying used ones which arrived with the same problem as those already fitted. Hope this is useful to someone.