Hi Tommy and welcome to the forum!
Yes, you can fit the
turbo instruments in place of your 70S instruments. They should be a straight swap and I'm sure the original wiring will connect. The only problem you may have would be if the
turbo uses an electronic speedometer and the 70S uses a mechanical speedometer (some 90's
Fiats had electronic speedos).
However, I wonder why exactly do you want to swap over instrument clusters seeing as your 70S instruments already have a tachometer fitted? This is the reason most people wish to fit an ugraded instrument cluster! If you fit the
turbo instrument cluster then you will have some gauges that will not function (boost, oil temperature and oil pressure). The oil temperature and pressure gauges will work only if you fit the correct sender units to your engine but the boost gauge will only work if you fit a
turbo!
Either way, good luck with whatever you do!