Fuel gage inaccurate

The fuel guage on my '97 2500 is really messed up. From reading full til empty is only about 11 gallons used (and I have a 35 gallon tank). I went to the Dodge dealership this morning and they said it would be around $300 for the sending unit and another $300 for labor to install it. That is an awful lot of money for a fuel guage issue. My question is, will the low-fuel warning light on the dash work as an indication of how much fuel I really have left, even thought the needle on the guage is very apparently wrong?

no sure if the fuel warning light will work, but i doubt it. but you can put the sending unit in yourself to save some $$. the hardest part is to drop the tank and the rest is gravy... should only take a couple hours if its your first time. just make sure u have very little gas in the tank when you drop it... it makes life much easier. i would also try to find it somewhere other than the dealership... it should be much cheaper. you could also check around to see if you can use a universal sender that would be cheaper as well... but when it comes down to it, i would go ahead and buy the proper parts since your truck isn't a $500 work truck... especially if you plan on keeping it for a while and don't want to have to redo it 5x.