You'd need a console with gauges because with that option the fuel gauge was moved to the console. I've done this conversion for a friend and it's pretty straightforward if you're handy with a wrench and understand wiring schematics. You'll have to take the fuse box apart and of course, drop the steering column to get the original gauge pod out. That's over and above all the stuff to add the console, which is considerable, for the oil pressure gauge needs a hard line, and the ammeter and water temp gauges need rewiring, the console will need its own fasteners and shifter hardware... etc. Figure in some serious downtime if you drive the car regularly. If you already have a console it's much easier to add the gauge pod to it, though, as was the case of my friend. I have no experience with repro tachs, but a good kit will have ALL the correct wiring to fit it into the original GM looms and fuse box as the factory did it. I don't mean to throw water on your idea, but it's not an afternoon job if your car doesn't already have a console. Good luck!