Gas Tank Cleaning - What do you do?

I was a dope and left some gas in the Healey tank when we took it off the road ~8 years ago. What was a brand new tank is looking pretty gross. 

What method/product/etc do you all use when cleaning out a tank? I tried the "Miracle" three-step method on the original tank. The cleaner and etch certainly worked well but the sealant clogged the pick up permanently (hence the new tank). I'd rather not go that route again.

I've heard of CLR working well but I would think I'd then need to neutralize the tank after use(?). What about re-coating the inside?

Have you tried a vinegar soak?

In reply to Patrick :

Nope. Just normal white vinegar? 

Baking soda solution after or just rinse and let it dry?

Vinegar, sit, turn, sit, turn, sit so you get all the rusty bits then clean it out with some dawn and get one of the tank coating kits

Dig, thanks.

I get a couple quarts of acetone and two handfuls of 2B gravel.

Dump it all in, swish the gravel in the acetone, dump.  It's not easy to get all the gravel out, but at least you know if there is one left in there.

I took my 100-4 gas tank to a radiator shop to be tanked, years ago.

In getting an old car back on the road after sitting 28 years with a 1/3 of a tank of what was gasoline I had to clean that tank of both rust and crud. I poured in a mixture of phosphoric acid and water and a length of chain. Sealed up all the openings, there were four total. Then with the help of my friend the owner of the car we shook and rocked the tank for a while, let it sit a while, and then repeated the process. 

We then flushed the tank with water,  poured in some denatured alcohol to remove the water from the tank and  let it dry in the sun.  I then poured in a tank sealer and again rolled the tank around to coat the entire inside surface.

The car is now running fine.

Thanks all, much appreciated. 

To remove the varnish crud I used MEK.  Worked like a charm, but it is evil stuff and demands respect.  For rust I used roofing nails in the tank agitated vigorously, followed by a rust dissolving acid (probably phosphoric.  Dried thoroughly with a heat gun and sealed tank with Bill Hirsch tank sealer.  Has worked for 20 years.  

sheet metal screws, roofing nails, etc, basically just go to your coffee can of leftover nuts and bolts and dump a mess of them in the tank with acetone or vinegar or whatever you're using.

In reply to AngryCorvair :

I spilled my coffee can of roofing nails and hurt like hell picking them up.  That gave me the idea of using them.