Isn't there a fuel gauge sending unit at the top of the tank? I'd suggest removing it and shining a bright flashlight down into the tank, or maybe using a borescope to inspect the tank for debris. I have one with a built-in LED light that I use for inspection of engine cylinders that will fit through any hole 1/4" or larger diameter, and it projects a full-screen image on my laptop computer. Very useful item, and they're available on Ebay for less than $50.00.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!