Bad gauges?

I have a 2005 v6 ford mustang and lately the rpm and the gas gauge have been misreading. At first the it was the gas gauge that was reading off then the rpm gauge soon after. However, sometimes the rpm gauge will be working right but my gas gauge is just completely wrong. The other two gauges are working just fine( temperature & speedometer)
Any suggestion on what might be the problem?

Sounds like a flaky ground, but I couldn’t begin to tell you where to look.

Chase