I have 1992 Sc 400 and kind of have the same issue, Except I changed the needles on the fuel and temp gauges, now the fuel go just a little below the half mark and doesn't move and stays there, and the temp gauge now goes up 3/4 the way and I ;ve it checked motor not running hot. Does anyone know about fuel gauge issues after changing the lighted needles? some mechanic said for fuel gauge motor needs replace and that over $300.00. Anyone ever had this problem or any ideas? appreciate the help