I have a spare Chevette 4 speed trans that was totally remanufactured. It was shelf stock in a transmission shop that closed. After 45 years in business, the guy sold all of his equipment and parts and retired.
In order to change or work on a trans in a BCW car, you’ll have to remove the engine and trans as a unit and tear half the interior out of the car to remove the “hump” that is rivetted in. I know…mine is still apart.
The transmission is connected to a welded-in plate on the crossmember. Because of this, you can’t simply drop it out the bottom of the car. In addition, when you pull the engine/trans as a unit, you can’t raise the trans high enough to clear the crossmember/mount plate…it hits the floor hump!!! What a nightmare.
I modified the plate to bolt in and out for allowing the trans to be dropped out the bottom of the car if it ever has to come out again. If you send me a private e-mail (firstname.lastname@example.org) I’ll send some pics.
All this was because the speedometer drive gear, the worm gear on the tail shaft, had disintegrated and I had no speedometer required for NJ inspection.
By the way, these 4 speed transmissions were from the Opel Kadett. Later Chevettes offered a 5 speed OD, but they won’t fit the TD replica’s without a lot of modifications.