1976 Rolls-Royce Silver Shadow Reviews, Pricing & Specs

I have a 76 silver shadow. When i put the vehicle in reverse gear the oil light comes on and the fuel gauge goes to empty. Have no luck finding a wiring diagram so i can trace this concern.

I recently purchased in an auction on Ebay a 1976 Rolls-Royce(A Florida car, I live in Pa.) The vehicle is in excellent condition. In S. West Pa. we only have a Berntley in Pittsburgh. Where is a good place to begin to purchase aftermarket parts(oil filters, air filters), etc.?

Since S. West Pa. has no known Rolls-Royce dealers, where can I purchase aftermarket parts for a 1976 Rolls Silver Shadow. The vehicle was purchased from a seller in Melbourne, FL. who bought it from an estate. Type of oil filters, air filters,etc.? I have an owners manual, five work shop manuals,and a metric tool set came with the vehicles. 57,000 miles.