[Ed]

Andrew-

I agree with Warthog and would have it sandblasted first. Then I would hand sand any spots they missed and then you need to completely soak the piece with metal etching compound and then follow it with a metal conditioner.

After the etcher/conditioner dries (read the directions...not very long)...you'll need to spray on a coats of Awlgrips' zinc oxide primer (it is a greenish/yellow in color and is very thin and runs easily...be careful) and then follow up with one or two coats of Awlgrip's 545 and then shoot it with Awlgrip or Awlcraft topcoat.

If done correctly, it should last a long time. Be sure to replace the zincs, etc...