Hello
I just joined this forum.

i have a an 85 g30 minnie winnie c class rv. recent purchase. my first Chevy ! 11,000 actual miles 350, 5.7 liters
It sat for many years

I recently pulled the dashboard out to replace the heater core. took the entire unit out. while the dash was out i had the radiator cleaned. i replaced the water pump, thermostat, upper and lower radiator hoses.Replaced dash bulbs with LED's. Big job. After putting everything back together the fuel gauge stopped working. shows empty. The coolant level goes over to 260 degrees, not suddenly but in a few minutes. i bought a gun thermometer and temps seem ok. 212 at the sending unit and cooler everywhere else. I've checked continuity on the circuit board. All good. Gauges worked fine before teardown. i am stumped. anyone have a similar experience ? Thanks in advance for any thoughts or ideas.