Help 92 c1500 5.7L

Hello ,new to forum I searched and found no answer as of yet hope someone can help, My truck has many problems dont know if they are related: Speedometer, cruse control ,temp gauge does not work and fuel guage stays 1/2 full unless i fill up. odometer does work,trip counter work and tach works , I have replaced the vss sensor,temp switch and temp sensor.sometimes while driving temp guauge will come up to temp and fuel guage will drop below 1/2 ,I think its the instrument cluster am i wrong?

might be a ground issue. I could be wrong here but I think each guage is direct. I had a similar issue with my speedo and it was the plug on the back of the tranny. Sorry could'nt help more. I would start with the grounds tho but thats just me

Thanks for you input, I will give it a shot.