Is there any reason why I can't put an 84 dash in an 82? Also, are the vents the same? Thought someone might know. Thanks

 

not all the vents are the same... the panel your vin plate is riveted onto is not transferable. even if you were inclined to snip the rivets... good luck not destroying the plastic on the 84 dash...
there are 3 places that you would need to modify on the upper part to allow the dash to bolt onto the top.
ianS did this swap in his <<

 

It will work. The main issue you will run into is the heater controls. If your lucky enough to get the whole dash assembly, you can use the heater controls from the from the 84 with the 84 heater box. I used the stock heater controls from my SA in my S3 dash swap. I had to modify the center radio surround to accomidate the controls. I even kept the SA cluster so I didn't have to rewire the dash for the S3 cluster.