New instrument cluster

You'll need to swap out idiot light oil pressure sending unit for one that works with guage. Fuel guage needs to be compatible with Mopar unit (same resistance range from empty to full). Check water temp sending unit & replace if it's caked in crud.
Yellowed "glass" can be cured with multiple runs of polishing with Brasso (works on plastic convertible rear windows, too). Go slow. Don't use a machine to buff as it may warp or cut plastic.
Mr. G's can provide a re-plated instrument cluster. However, you'll need a good core. I don't recall if he replaces the "glass" too.