I'm in the same boat as the original poster. I want to put one behind the axle but don't know which one to use. I'm kinda on a budget but don't mind paying $150 - $200 for something that fiys. It needs to have a top filler also cause I can't afford the bodywork to go thru the 1/4 panel. I would really appreciate some help on this as it is my next step I want to get done. Any info about filler necks, sending units would be good too.