That's pretty much the plan; but replacing the gauges (housings) is the easy part.Well, if they keep the dimensions the same, you'd think you'd be able to take the whole cluster out and replace it with a real cluster.
The hard part is making them work with the electronics that are in there from the Elgin.
I also have to work out warning lights, turn signals, lighting, correct OHM from gas tank sender, oil pressure sensor and splitter so idiot light will still work, highbeam indicator, etc.. Plus looking into GPS Speedo, how much more <$> with it?
Then the how to pull it out, so you don't destroy it; always kind of an important part when you go to put it back in.
That's why I said earlier "the devil is in the details"