Can you take a photo?
I literally just did my '86 190Es pad. It was a small one (not the full size you probably have). It had no clips, but they sent me some with the new pad.. but there was nowhere for them to go. I just used the adhesive on mine, and that should be fine for you.
How much did your replacement pad cost? Here in the UK mine was £25.
2.5-16v 1990 90,000m Astral Silver
2.0E 8v 1986 107,000m Black