I got an 84 Trans Am and im not too fond of its plain-looking dashboard. I was thinking of changing it with that of a newer TransAm. I know they look like they have the same dimensions, but will it be a direct swap? Has anyone here done this before? Also my stock speedo is the 85mph one, can i put the 120 or 140 one? what kind of speedo gear should i get and from where? I have 3.42 gears out back.