This is a New Shift repair kit for IH "56' and "66" series tractors (This will not work on 656 or 666).
Shift linkage sleeve, part # 404855R1
Reverse shift collar, part # 529490R1
range shift collar, part # 529489R1
Main collar, part # 397987R1
The bushing in the sleeve is not included and will have to be purchased from a Case IH dealer or other source or reuse the one in your sleeve (they are usually good).
This kit replaces the worn linkage at the shift quadrant of the "range" lever. This kit is not a revision of any type. It is meant to replace the worn shift lever components back to the original specs. It does not change the shift design. With this kit installed correctly your tractor shift lever will feel like it did when it was new.
Fits IH Tractor models:
756 766 826 gear drive 856 966 gear drive 1066 gear drive 1456 1466 1468 1566 1568 21456 2756 2826 2856
I have over 30 years experience of rebuilding IH tractor and motors and have many parts available. Email your questions and I can probably help you.