As always, searching the site should point you helpfully. In particular, check out the currently active thread on this in the SL forum, which has detailed directions.
'97 SL500, 40th anniversary edition
'04 Olds Bravada (SWMBO's)
'06 Lexus ES330
'89 560SL (sold)
SL--Anything else is just a Mercedes.
(Kudos to whoever said it first)