The only way to do it is cut out the bad metal, make patch panels and 
weld them back in.  The patch panels don't sound that difficult to me, 
especially since most of it will not show.  You may have to do some 
grinding and use some bondo, but bondo over steel is better than bondo 
over fiberglas.
      Larry Young
On 5/18/2015 10:50 AM, James_ via 6pack wrote: