Matt, I don't guess you were being ripped off.

Specifying a speedometer by the K number isn't enough. The K number is for the ratio determined by the tire size.

The "side board" you are missing is for the service reminder light function. This feature puts on the "service" light every 5000 miles so you know when to change your oil. I don't think you really need that. The panel changed in 88 when the light was added, so your new one is probably an 86 or 87. It changed again in 90, when the airbag made it necessary to bring the reset to the front.

I'm sure sellers of these parts may imagine one size fits all, but it can be a stretch. Buyers must be wary of the differences year to year.

(I did see your photos you emailed me off list. On second look, I can see the date of manufacture, 11-85, clearly on the new board.)

--
Art Benstein near Baltimore

A Navigator's Definition of Latitude & Longitude: Latitude is where we are lost, and Longitude is how long we've been lost there! - USAF Navi-guesser