First off, I just ordered a new fuel system today for my 53 f-100(tank, straps bolts, fuel line etc) Should I coat the inside of the tank with some type of protection? Also I have an old tank for anyone who may want it. it needs cleaning but does not leak!!

 

You can check with your tank's supplier, but I would think it should be made and sold ready-to-run. I would be disappointed to pay that kind of money and then be told I still have to seal the inside. It should be made from coated steel or other non-corroding material, ie; stainless, aluminum, plastic.

 

Tanks are easy enough to come by. I wouldn't bother if it was me.

 

The crap I had to go through with ethanol in my 89 wagon... I coated the inside of the new tank.
Maybe if you just use ethanol free gas you wouldn't have to worry about it.

 

If you seal it, be sure the sealer is compatible with gasahol. Most of the sealing compounds were originally designed for use on light aircraft fuel tanks to reduce risk of corrosion from condensed water vapor on standing. Aircraft gas does not contain ethanol since ethanol is hydroscopic (absorbs water).

 

I wouldn't go through the hassle and then have the slightest chance the sealer could flake off and cause problems. Like said above, the new take should be good to go. Just make sure you keep a good level of gas in the tank.