Make sure you're using enamel paint. Latex or Acrylic paints will always have a bit of "give" to their finish and can stick, even after several years. Enamel will cure hard and should not stick. If sticking is a continual issue, try wiping a tiny smear of silicone grease on the peg, the needle should never stick again and the silicone grease won't ever dry out.

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Current stable:
1995 E320 149K (Nancy)
1983 500SL 120K (SLoL)

Black Sheep:
1985 524TD 167K (TotalDumpster™)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)