On Mon, 13 Nov 1995, Sami Dakhlia wrote:

> ... Cleaned them up in hot, soapy, water and let
> them dry for a couple of days. Then painted them with POR-15 (paint over
> rust), which gives the metal an almost ceramic-like, hard, finish.
> Finally, I band-aided perforations with aluminum-foil tape, and voila.

I was fortunate enough to have heater boxes on a type III that had minor 
rust damage that I braised up, then glass beaded the sheetmetal, and finally 
had the units aluminum coated like some manufacturers do to prevent headers 
from rusting.  The results were excellent and are still rust free 3 years 
later.  The downside $$$, and you need a good solid piece of sheet metal to 
begin to work with.  It also made the engine compartment look very nice and 
clean until a pushrod tube started leaking.

PEJ