fuel senders for dummies?

[Bakenaz]

I searched and read many posts about testing senders and gauges and i think i am just simple. Even this site sorta helped http://www.6066gmcguy.org/Electrical-02.htm
The problem is that when my truck is in the run position the needle goes directly to E as in pic:
Then when I remove the wire from the sender i goes to 9 o'clock:

While key was on, i tried grounding from post to flange with no movement of the needle. I have a 69 I6 250 manual trans. here is the new sender.
Any help for the simpleton would be great. I currently have a full tank of gas in thse pics. Thanks