Tie wrap idea won't work, the metal ears are angled such that a filed notch still won't hold the tie wrap securely. Also the bottom is close to the metal track so it may wear and cut the tie.

Since this regulator has one good "tang" I'm not going to modify it. When I take the one out of my car, I plan to drill small holes on each metal ear for a small sheetmetal screw. It only has to hold the plastic to the metal piece. The vertical force is on the single metal rivet and square plastic feature.

This regulator was built for a smaller window that doesn't get much usage. The front scissor type regulator is a more sturdy design (no cable and intermediate plastic piece) but used frequently. What's curious is the single pin that I assumed was designed to rotate to facilitate regulator detachment from the window. It would be better if it had a snap-in design but it was assembled by sliding it under the tangs and then riveted. Take a look at the all metal Porsche 996/986 regulator on the right for comparison.

Attached Thumbnails

   

__________________
'88 300TE, 175k, black RENNTech 3.6L Recaro C's AMG 1 SOLD
'92 500E, 110k, Spruce green, stock SOLD
'94 E320 Cabriolet, 130k, E500 wheels, Emerald green SOLD
'94 E320 Cabriolet, 110k, black, stock, SOLD
'88 300TE, 229k, dark grey, SOLD
'90 300CE, 212k, white, new paint, SOLD
'91 300E, 209k, white, rebuilt head SOLD
'74 914-6, grey, 2.7L 325hp twin turbo Audi conversion