Fuel gauge inop?
 

I am not sure what is the problem.
My gauge reads over a 1/4 tank when the fuel light
comes on and at that point will take about 15 gal. to
fill. This is on a cd and I have no idea what size tank is
in it. It has always done this since I have owned it(last Nov.)
Sending unit? gauge? low fuel light? other?

gunk on the sending unit.
pull the med kit out and start opening her up...

Likely due to crud in and on the fuel level sender, which is located in the tank. It is accessible thru the top of the tank after removing the 1st aid kit, if coupes are like sedans. Takes a large socket I believe, and much care needs to be taken with the thin wires once you have removed the sender. A good first approach would be to search this site with key words like 'fuel sender' & 'cleaning'.