The heavy
undercoating actually made things worse, by trapping moisture along the
firewall and eating away at the sheetmetal. This is a before shot of the
passenger side damage, prior to heating and scraping the undercoating. |
I was originally planning on trying to salvage the cab corners from the
yellow cab, but after spending some time trying to cut the old ones out
and taking a look at what I'd be in store for trying to fix them, I
decided to just spend the $20/each to get replacement pieces.
Using a torch, I heated up the undercoating and scraped it off the
firewall, and then cut firewall patch panels from the '70 cab, as shown
here. Keep in mind that this cab is going to be completely sandblasted, as
are the patch panels I cut, so the patch panels shown here are very rough
at the moment. |
Here's the
passenger-side firewall after cleaning off the undercoating and trimming
out the rust, using an air hammer with sheetmetal attachment. I plan to
weld a patch panel using a lap weld with about a 1/4" overlap, using a
Hobart 175-amp MIG welder. |