Call your local GM dealer and ask the parts department personel the question. You may have to refer to the "service parts identification" sticker located in your glove box. This sticker will have a list of 3 letter/number combination codes on it. At least 2 of these codes that start with the letter "M". M codes describe your transmission. Most parts people can use their computer well enough to look up that info for you very quickly.
yes
YES they are the same.
glow plug issues, head gaskets, water pump, and the allsion tranny wasn't great either.
Yes. It may be bigger but it will bolt on.
It should be a TH700-R4
That would be a 4L60E trans.
The 400 tranny on a 1983 Chevy 6.2L K20 diesel have very high pressure.
inside the tranny
It depends on whitch tranny you have. If it's a stick the switch is located on the right hand side of the tranny. If an automatic the switch is on the top of the tranny.
no the bell housing is different as is the spline for the clutch
on the tranny in most cases
a 1983 silverado has an TH350, its a three speed tranny. its been said that it's the best transmission that gm has ever produced.