The filter is under and forward of the fresh air damper (flap) that Naj shows. This damper is controlled by the lever with the blue arrow. The filter is available from MB, I can get the part number tomorrow. Access entails removal of the chrome from the intake cowl, three screws, two screws on the back of the cowl in the wiper shaft wells, two screws in the front of the cowl under the chrome and four screws inside in the rear of the cowl that just need to be loosened. Then the cowl lifts off. Then the two bolts on top of the damper and remove one bracket and then the damper can be slid out of the other side. Lift the tab on top of the damper and it will flip open for greater access and then slip the cable wire out of the mounting point in the damper. Off it comes. Then you will see the filter toward the engine compartment. It's a good time to clean up everything in there, wipe it out, clean the drain holes and treat the rubber gaskets and seals with rubber treatment to soften and preserve. Check the heater controls to see that those dampers are opening and closing properly as well as the heater water valve under the grommet in the firewall. The original air filter had a fabric tape wrapped around it where the damper lever mechanism rubbed on the filter so it wouldn't rip. The new one didn't, so I wrapped a piece of duct tape around it.
I didn't try it, but perhaps the filter can be changed just by lifting the tab on the damper, rolling it open wider, and changing the filter while it's in place. It's so easy to remove though, that I'd use the opportunity to check and clean the area.
John
1967 Early 250 SL Red/Caviar, Manual
