I have checked the DIY articles on door panel removal but I wonder if someone would help me diagnose before I remove the panel. I would like to have the parts on hand if possible to fix the problem while the panel is off.

My drivers side window will roll up to the point where it touches the top seal but will not travel the last quarter inch (I can push it up easily with my hands on both sides of the glass). There is a quick loud rat tat tat when it reaches the top of its travel. The noise continues as long as I continue to press the up switch. The noise sounds like it is coming from just below the lock knob behind the door panel.

If someone knows what I'll be repairing I could go ahead and order the parts and just remove the panel one time. Any help appreciated. Thanks for the DIY articles too. I did not see any DIY on actual window repairs or adjustments but if someone can point it out if one exists I would be grateful.
I have a 1994 e320 wagon.

Ray