A new OEM General Motors Transmission Gear Housing Adapter Sleeve (Bullet) that I got at an auction of vintage car parts.  This is part no. 345215 (same as 25513247).

The 19-tooth Speedo Gear in the photos came attached to the outside of the GM box with a rubber band.

I can't find this part no. in my parts catalogs but the instructions are dated 1972 if that helps. If anyone knows what this is for please email me.

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