There are three versions of the T-50 that I know of. One is pre 1979,
and has a different bolt arrangement between the bellhousing and the gearbox.
The 80-82 version has a the same bolt arrangement as the 83+ T-50's, but
a different (smaller) output shaft diameter.
The tailshaft or gear shifter housing on the '80-87 T-50 transmission
is longer than the '70-79 models by about 6". The main reason for this
change was to bring the shifter further into the passenger compartment.
I remember that in my pre '80s Corollas the shift lever came out from the
lower part of the dashboard, compared to my later models where it comes
out of the floor, just ahead of the seats. If you run a car in competition,
you may want to use the older transmission with the shorter shifter housing.
The lever on these models acts directly on the shifter forks. The newer
model's shifter must act through an additional linkage, which adds additional
vagueness and is less durable, especially when ramming the lever during
clutchless shifting. Most later model shifters ('80-87) with high mileage
or hard use will be very loose. In almost all cases this looseness will
be due to a collapsed nylon bushing on a ball joint at the end of shift
lever in the transmission. This bushing cost less than $2US and is easy
to replace. Warm the new component in hot water before popping it on the
lever to prevent it from breaking. The early model shifters don't have
this problem because it doesn't use the extra linkage and everything is
metal to metal, no bushings. If you are replacing this bushing, you might
as well remove the other source of vagueness, the rubber bushing in the
shift lever rod. It is located about half way down the shifter where the
rod bulges. As the years progressed, from 1970 on, this rubber bushing
got bigger and bigger in order to increase isolation (vagueness). With
the engine off, try to pull the lever down into any gear with increasing
pressure and see how much the lever flexes. This movement is due to the
rubber bushing. If you truly want to "experience" your machine, remove
the rubber bushing. I must warn you, though, that if you grind a gear badly,
you will "feel" the mistake all the way up your arm and hurt along with
your machine. The best way to eliminate the rubber bushing is to: - remove
the upper part of the lever with the bushing - weld a hollow tube to the
bottom part of the lever - weld a stud to the end of the tube for your
shift knob - while you're at it, why not make the lever 1" shorter for
shorter throws P.S. I believe that the only difference between the '80-82
(3TC) and '83-87 (4AG,3AC) transmissions were the bellhousing. You should
be able to use a short tailshaft '70-79 (direct linkage) T-50 in '84-87
Corollas by using the bellhousing that came with the car. You would also
have to cut the shifter hole further forward on the trans. tunnel and likely
mix and match driveshafts halves.