Piddled with this one a bit more on Saturday. Since I previously dropped the gas tank decided to clean up those parts.
Used the following items to clean the original 20 gallon tank rubber mat pieces.
Nothing was a miracle worker, took a bunch of scrubbing and picking out all the little pieces of rusty metal out of the rubber with the small sharp pick pictured above. No before picture, forgot, but the mat pieces were pretty rust stained. Came out pretty good.

Took the sending unit and hoses off the tank. Quick before reference picture.


The fuel gauge was the only gauge not working in the Jeep. Someone replaced the sending unit in the past judging by the hose clamps on the supply/return rubber hoses.
First surprise, crappy float, maybe the cause for the fuel gauge that always reads "E". The floats that look like this will typically crack, fill with fuel, cause the float arm to rest on the bottom of the tank and the gauge read "E". I'll test this float and see what's up with it.

Second surprise, pick up sock/filter fell off the pick up tube. Not sure how I was able to run all the fuel out this Jeep, maybe the sock fell off after I removed the tank???

The "scale" part of this sending unit still looks pretty good, maybe the float was the issue?
Spent some time cleaning up the plastic tank, cleaned up really well. Will post up a finished picture later. A few pictures of some random factory markings on the tank.
