The lifting angle is three separate parts, riveted together -- the replacement is the entire sliding section for each side. The new ones are much sturdier than the old ones. Cost me about $95 each.
To remove, remove chrome slide rails, liner, roof panel, and rain gutter on the rear, unscrew from translation bridge (three screws on each side), slide lifting angle to forwardmost position, and rotate out from channel. The entire sliding portion comes out. The translation bridge will probably be wedged sideways and you will have to mess about with the manual crank and have someone pull and push to get it to move. If you cannot get the roof panel to move back far enough, you will have to pull the liner out from the bottom -- this is tricky and can ruin it.
Hook replacement into channel after lubricating all the felt sliding pads with MB sliding sunroof paste (don't substitute, this is special stuff!). Install translation bridge, rain gutter, and sliding panel. Get the manual, there are a number of steps and they all have to be correct or the roof won't work correctly!
There are a number of posts on this subject from this Fall on the forum -- look them up and see what you are in for. Not a difficult replair, just takes some time to get everything right! You don't have to assemble the lifting angles.
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!