722.1 transmisson speedo gear housing
 

have this 772.1 trans 4 speed does anyone know how to remove the housing for speedometer driven gear which attaches to speed cable

If it's similar to the 722.3, which is located in the tail housing of the transmission, you need to remove the yoke from the end of the output shaft first. After that's off it's simply a matter of removing the tail housing. Not difficult really.

There are some shims in there you need to be aware of to ensure you put them back in place in the correct order. You should replace the gasket and seal before putting it all back together.