On the W126 their are actually 5 here you go:
115-992-03-01 you will need 1
115-267-12-50 two needed

The shifter boot is probably shot and only $12.43
126-267-02-97

You will also want to change the shifter light builb while everything is open.

One thing that I didn't change that I think I should have is the little spring that puts tension on the shifter. It has two little bushings on its base. The dealers diagram will show an exploded view of the shifter and you can figure out the part numbers. Also their is a rod that comes from the trans and attaches through the first bushing. A little clip holds that rod in the bushing get that clip your old one is probably shot.

Also the gasket between the shifter and trans tunnel 126-267-02-08 is no longer availible.

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2016 Corvette Stingray 2LT
1969 280SE
2023 Ram 1500
2007 Tiara 3200