SLman61

Hello on my sl500 my dash cluster the illumination lights don't work.all other idiot lights, milage and outside temp does light up
I bought another used one and swapped it out. Well problem is my car has 96k original miles.
And this one has 169k so my question is can I swap circuit boards from one cluster to another and keep my cluster? Also the fuel gauge on mine doesn't work and the one I bought works great can it be changed as well?
And changing circuit board will the milage change with it
Thanks