1978-1979 Rear End Cover Changes

When GM changed the rear end cover in 1978 to part number 464909, there was a foot note added to it.  The rear cover holes and pattern changed so other parts were needed to install this cover on the 1977 and prior cars.  Below is the picture of this change from the 79 AIM as well as the notes from the parts catalog.

464909 Rear End Cover Note