Simple answer...yes. Not much changed between the years until 81.
no it will not fit
Anything will fit any car, anytime. That is hot rodding.
Yes...it absolutely will. In fact, you can change them all from 1970-1981 if you have all the parts from the front end to do it.
Does your Firebird have a Chevy or Pontiac motor in it?If it is a Pontiac motor, you will need an adapter from Summit or Jeg's.Also, it could be a different output shaft length and spline count.
NO!
Yes but you require the front bumper brackets, and lower valance, signal lights and brackets. I have done it, can use 1976 hood with it also . 1977 and later hoods are flat and will not allow bumper to fit correctly
No
Yes.
Yes it will fit, They are exactly the same body style
Yes it should.
Yes
Some parts will fit, depends specifically on what parts you're referring to