Where is this located, im fed up of having to guess how much gas i have. I need to replace it

 

inside the gas tank, attached to the pump I believe

 

Its actually riveted to the bracket that holds the pump. You either need to drop the fuel tank, or cut a "hatch" above the tank. To replace the sending unit, you have to buy the entire pump support basket, which I believe is over $200.

 

There's 2 styles of sending unit brackets and buckets. One that holds the bucket to the sending unit bracket with 4 rubber studs and the other style bucket clips on the bracket. If you get a new sending unit, try to match the style you have and you will be able to use your old pump and bucket with out prying off the lid of either bucket should your pump die. or in other words you can interchange buckets easier since the pump is inside it.
If confused I can email you pics of both styles sending units.

 

damn i thought it would just be a little sensor.