Gas Gauge Fluctuates with acceleration! HELP!

[PROLAZCO]

Alright guys (and gals), my gas gauge misterously decided that it was jealous of my speedometer and it was tired of staying still, sooo now whenever i accelerate my fuel gauge drops... heres a video, please watch them all the way through for the full understanding. thanks in advance.

edit: i realized yesterday that the low fuel light on the gauge still works properly... sooo does that mean it cant be the fuel level sensor?

http://www.youtube.com/embed/T_c8c2OVyVI

http://www.youtube.com/embed/aXD8BXfwH-I

[dnguyen1963]

Remove the cluster and tighten up the ground nut behind the gas gauge. Remove the fuel sender unit from the pump assembly and clean it really well with carb fluid (spray inside the sender and shake the sender up and down rapidly 5-10X - repeat until carb fluid is clean).

[PROLAZCO]

I have a cabrio so I know there's the 2 caps under my rear seat. Where is the fuel level sender located? Thanks for your help!

[dnguyen1963]

passenger side