fuel filter/gas gauge
 

here is the scenerio, any help is greatly appreciated...i have a 1965 mustang. my gas gauge will jump to about 5/8 a tank when car is started. there is an after market inline fuel filter installed. the stock fuel filter on the firewall isnt connected, but wires from the dash are still connected to it. i am guessing this is why my gas gauge isnt working properly because its connected to a disconnected fuel filter. i really want to remove this filter and just use my inline one, but i cant figure out where to connect the wires that are connected to the stock fuel filter. any suggestions? i hope my explanation wasnt to confusing...

Got some confusion going on here. There should not be wires connected to a fuel filter. The wires go from the sending unit at the gas tank to a constant voltage unit under the dash attached to the instrument panel. You should get a wiring diagram. They are available from:
http://www.themustangshop.com/
Go to the online resources page.