I've got the manual and had familiarized myself with it, but because the broken parts had been previously removed by someone else, I wasn't getting the rivet thing straight in my mind. What I have, apparrently, is part of it... derivetted(is that a word?). Your explanation clarifies it perfectly and I've already disassembled it, so I'll get the parts and do it next weekend. Thank you, Bruce.
The Golden Rule
1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)