I recently got a 1990 5.0 gt 5spd. I finally got a tag and ins. and started driving it. I noticed the gas gauge kept saying full,:shrug: the guy said he filled it up before we loaded it up on a trailer. After around 120 miles I decided to fill it up, especially since the gauge kept going farther up past the full mark until it was buried behind the dash. I tried the search to no avail so, how do I fix this. Could something be mis-wired so to speak, new sending unit or what? This is my first 5.0 and I'm not as smart on these cars as I would like to be.