727 speedometer gear

Yeah their easy to change. What I do is jack the car up from the rear axle as high as I can get it and put stands under the axle. Jacking it up this way causes the ATF to run forward so none (or a very minor amount) only spills out when removing the gear housing. Clean the area around the gear housing good with brake or carb cleaner and take note of the 3 sets of numbers on the housing. There's a little raised tab near each set of numbers that has to be aligned with a raised tab on the extension housing at the bottom. For example, if you are installing a 34 tooth gear you'll want the tab by the numbers 34-38 aligned. Here's a picture that shows you what I'm talking about. You might also want to change the seals on the adapter while you at it because even if their not leaking now R&R'ing them might cause a leak. You should be able to get them at your local NAPA but if you have problems finding them PM me and I'll send you some

Torqueflite speedo adaptor.jpg