At 09:37 AM 10/20/2009, you wrote:
>... when the gauge is at the halfway marker, the odo shows around 90
>miles. The fuel gauge drops more slowly after that, so middle to
>bottom of the red is 240 or so miles.  90 miles above the halfway
>tick, 150 miles below it. Not very linear.

Not at all linear.  Mine is similar (except now the top of the white
mark just above the red band seems to be "empty.")

I think the white ticks, top to bottom, are "full," "3/4," "1/2," and
"1/4" or something like that.  They just didn't make any effort to
make the scale linear, but instead reflected whatever reading they
get based on the shape of the tank.