i just received my new gas tank from classic. my buddy says we should use por-15 on the outside to prevent rust. it looks like the tank has already been treated with something.
do i need to treat or not?

Its been my experence that POR works best on somewhat rusty metal. I would not do it. I would not put any thing on it. Maybe dull clear,but sometimes that looks milkey, or you could use tank tone but it won't look original. If you keep it reasonably clean it will last many years as it is. Just some wax maybe.

I cleaned off the oily protective coating that the tank's come with, using POR marine clean and then POR etching and then 2 coats of POR Clear "paint". So far so good. POR works great on clean, non rust surfaces if its prepared right. :thumbsup:

http://www.carsbyjim.com/storage/GasTank/DCP02528.JPG