Be Gone Demon Rust!...

Strange things happen during the course of a project.  I'm positive I took pictures of the old rusty parts being removed
from the drivers side floorpan. Where they are now I don't know.  If I ever find them I'll post them on the site.

Several years ago in an issue of Mustang Monthly magazine I saw an ad for door braces to stiffen the chassis while
a car was on a rotisserie.  They tied the rear door jamb to the hinge post and also the transmission tunnel.
 Since I knew this car was going to have some major structural pieces replaced I thought I'd better
build something to hold things straight.  A trip to Home Depot for some square tubing, 7-11 for a slurpee
and a couple of hours one night yielded these braces.  I added one additional bar to the design that I saw earlier
and ran a vertical down to the floor to keep the cowl from sagging.  I have a long threaded foot at the bottom to
allow these to be used again in the future and adjusted to the height of the car.


Here we can also see the supports under all areas of the car.  It is extremely important, especially in a convertible,
that nothing moves while structural parts are out.  If things do shift and stay misaligned when the new parts go in its going to
take a lot of bondo to fix that.  When I was a kid my family owned a travel trailer and used threaded stabilizers in the corners
to level the trailer.  Since jackstands aren't infinitely adjustable I thought some of these stabilizers would work better in various
areas allowing adjustment.  I went to great effort to level the car fore and aft and also side to side.  At the rear I have two
pieces of half inch plywood running down to the floor and bolted to the car using the bumper mounts.

I told you we were doing major surgery here.  This shows the inner and outer rockers removed, the floor
from the firewall to the rear seat plus the front torque box an outer cowl.

A closer shot of the cowl/firewall.  Like I said, when you start digging in the rust is
always worse than it appears on the outside.

The first step to repairing the floor is to replace the front torque box and sub rail that passes below the drivers
feet area floor pan.  In the center of this picture you can see the angled end of the frame rail that extends from the
firewall to the radiator.  On the outer side of this rail is where the torque box mounts to connect the inner rocker
panel to the rest of the vehicle.  This frame rail continues rearward till it meets another box (under the floorpan)
directly under the seat.  I have no pictures of that box as it was removed from the car.  Note the two holes just
below the dash on the firewall.  I wanted to keep those original as they are the factory locations for the
park brake and speedometer cables.

New shiny parts going in!  Here we are test fitting the inner rocker (left) bottom and front plate of the torque box
(middle) and the sub rail (right)  Using the door post as a reference here.  By ensuring the car was level before
cutting out the old inner rocker panel and doing the same with the new things should stay aligned.   A word
about reproduction parts.  They are just that, reproductions, not factory Ford built parts made from Ford stampings.
 As a result their fit is....well just say less than perfect.  Most if not all repro parts need some tweaking to get them to fit
.  I have discovered that this isn't just limited to Mustangs but all makes and models.  However, having said that, I
believe there is a difference between tweaking and rebuilding.  Not shown here is the angled piece of the torque box
that will be installed from the top to the bottom of the L shaped part you see here.  Between the L and the angle
which I bought welded together as one piece (and didn't fit) I cut them apart into 7 indvidual parts to get them to
fit and weld them back together into one.  Needless to say this was an offshore part.

Now we can see how the upper plate of the torque box fits.

With everything modified to fit like we want we can now start welding.  This is the bottom plate of the front torque
box welded in and painted in epoxy primer (blue)  in the middle and weld thru coating (grey) around the edges.
The weld thru coating (made by 3M) is great stuff since it allows some corrosion protection in areas that will be
welded but still allow conductivity for the welding process.  You can also see the new sub rail
off to the right of the torque box.

Now that the front torque box (lower plate) is welded in we can use that as a reference for repairing the rear torque box.
 The rear torque box provides the same function as the front in that it ties the inner rocker panel to structure closer to the
center of the car.  In this case the rear frame rail, which starts under the rear seat, travels over the axle and provides a
mount for the rear bumper.  In this picture we can see the new inner rocker and the existing rear torque box.  There was
a significant amount of rust at the bottom of the box where the floorpan sat on top of it.  Sandwiched
metal is a breeding ground for rust.

Once the upper layer of the torque box is removed you can see the extent of the rust damage below.  There
are replacements available for the upper plate.  The lower plate is not available in reproduction.  It is one of the
few 65-66 Mustang parts that is not reproduced.  Time to fabricate a new one from some 14 ga sheet.

Here is the rusty parts of the lower plate removed and the remainder sandblasted clean.

Another shot of the same.

It's hard to see in this pic but the vertical part of the box on the left side with the
flange bent to the right has been rebuilt at the end closest to the camera.

This has the lower plate installed and primered for corrosion protection.
Again the edges where welding occurs the weldable primer will be applied.

We now begin the fitting of the new upper plate of the torque box
.  The notch on the right side is where the inner rocker fits.


Now the upper plate is welded in.  Rear torque box repair is complete.