headlamp lens on e34

You have to remove the centre section grille first, one 'screw rivet' in the centre under the bonnet, then prise the top away, then feeling under headlamps release clips holding the outer ends near the wings in place and push the panel outwards (it's all in one with the kidney grille and the strip running side to side beneth the grilles) then remove the screw rivets holding the grille  and a phillips screw into the front corner of the wing, and remove, you can then get at the headlamp fixings, give the nylon bayonet pieces a quarter turn and release.

afaik, you have to replace the whole lamp, lenses are sealed on.

It's not necesary to remove the bumper.