So, next up was finishing the tank...
When I thought I was done, I took the tank to work, and pressure tested it by hooking up an air line (with regulator) and spraying it with soapy water. Anywhere you get bubbles coming out, there is a hole. I had a few pinholes, either where I missed the edge of the plate (oops) or had a pinhole in the weld. I patched them up and was ready for the next step.
I hole sawed the 3 holes I needed in the top of the tank, 1 for the fuel pickup/heater, one for the tank level sender, and the one I almost forgot.... the fuel fill. I wouldn't have gotten very far without that one!! Once I finished the tank, I cleaned it off and primed it with pro-form self etching primer. Once that was clean, I painted it with the spray on box liner. Not really all that impressed with the stuff, It wasn't what I had planned on using, but they were out of what I wanted. I was hoping for Pro-form box liner that you roll on. We use it at work frequently and it gives a really nice grippy finish when applied with a stucco roller. I think I might re-paint the back of the tank when we have some extra at work. (the back will see the most wear from trunk item "rubbage".
The fuel fill is currently just a weld in 2" NPT "tank flange" from Princess Auto. I tried to come up with a better fill... but this was just the easiest. I can always change it later! The level sender is also from Princess Auto, very basic and standard float type sender. Now, I bet you're looking at that nice stainless steel tube in my hand...
That's my NotFox®©. Just kidding - it's not copyrighted or registered. I either figured out how they make a hotfox, or I came up with a new design - I've never seen the inside of a hotfox so I don't know. I do know that it cost me a LOT less than a hotfox. helps when you have buddies who TIG all day long. If I can get enough interest in these pickups, I'd consider fabricating a few - not mass produced or anything (unless there is a demand!). Like I said, it was a lot cheaper than I could get a hotfox for, so I did it. My tank is 14" deep, and this goes about 13-1/2" down. I wanted to leave a bit on the bottom for a final protection against goop sucking uppage.
So with the tank painted, it was time to start installing all the bits. The access port is held down with a whack of #8-32 machine screws. Drilling and tapping all them took a bit of work, but was totally worth it.
Here is where I made stupid tank mistake #1. The plan was, with that nice big rectangular hole... to stick my arm/shop vac inside the tank and get every last bit of steel & dust out of the tank. Can you guess what I did? First thing... sealed up and bolted down the nice big plate. Then had to vacuum out all the crap through the small holes.
Then I had bright idea # 1

Stick a magnet on the bottom surface of the tank just below the pickup - this way if there happened to be any small particles of steel left in the tank, they would stick to the magnet on the way to getting sucked up by the fuel pickup!! YAY... I'm smart again!!
Now, you note that there is a #1 stupid mistake, that should lead you to believe that there is a #2. You are correct. Just after perfectly placing the magnet of bright idea #1, I flipped the tank up on end to get all the last bits out with the vacuum. I have NO idea where the magnet went, but it's NOT in the vacuum.

So I now have 2 magnets in my tank, one of which is just under the fuel pickup.