guy - my 2¢ - the metal clean is to get any trace of rust out of little pits nooks and crannies so it can't do what it seems to have done, carry on rusting below a primer that's not waterproof - the sealer is to make the primer waterproof
since ya don't have the cash to start over, yer best bet is to get bare metal, use metal prep, use yer Dupli primer, sand it out as necessary, use a sealer, get'er painted soon as ya can
and buy the wife some dark chocolate for good luck
Bill