From when I acquired the car around 25 years ago, the electric sunroof has always had a variety of problems. The most noticeable was a loud grinding sound from the motor in the trunk. I discovered that the issues were a cable that had been torn up (Picture 1 here) and greatly worn motor gearing.

Over this year's summer months, I have spent a *great deal* of time carefully observing, studying, analyzing, and correcting a variety of additional issues with the sunroof (e.g., worn out rear seal, worn out rubber-felt slider shoes, bent and improperly installed front slide angle, damaged wind deflector lever, damaged height adjustment pad, damaged wind deflector spring clip). All required replacement.
Incidentally, I have receipts from the car's second owner that document M-B dealership staff doing various sunroof-related things decades ago.

But the one prevailing issue (that I suspect led to the severe cable and gearing wear and failures) is this:
When using my hand and arm to slide the sunroof back from closed to open, there is a definite point (Picture 2) at which I must apply significantly more effort to continue sliding the sunroof back to fully open.

After *a lot* of observing and measuring, I am fairly confident that the cause is this:
The approximately 16" cable tube (Picture 3) attached at the rear of the sunroof frame and that the sunroof's female tube slides over is slightly bent at about 2/3 of the way from its forward end and in general is clearly sloping upward from the rear attachment point. The spot where I observe this slight bend with my eyes corresponds with the point where the end of the sunroof's female tube reaches it and I feel resistance start when sliding the sunroof back with my hand and arm.

The tube has been formally discontinued by M-B and despite much searching online, I have thus far been unable to find a new or used replacement. Through observations and studying the FSM, it seems that the tube is rather unpleasant to access but it also seems that I either must replace it or straighten it.

So:
How might I go about straightening the slight bend in the tube? Plus, possibly straightening the rear end of the tube and/or the attachment point?
I would appreciate any ideas of suggestions for how I might go about addressing this situation.

Thank you.

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