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When I last posted I was getting ready to purchase patch panels for my cab. I was looking forward to digging in to the rotten metal. Before I could order the parts, my son informed me that I needed to wait until after Christmas. Christmas day came and I happily feigned surprise at the new patch panels my wife bought me! Then our weather turned for the worse (tons of snow, then tons of rain) and things at work (protecting our assets from flooding) took precedence over my project. About two weeks ago I was finally able to get going in earnest.

After surveying the damage to the floor pan on the driver's side, I decided I had to remove the seat riser first. It has its own damage (some of it man-made by a previous owner) and working on it up on the welding table would be much easier anyway. The first photo shows the floor pan after removal of the riser. I simply cut the riser off where it joins the back piece, then worked my way around the bottom lip with a very thin chisel and hammer, lifting the edge up to locate the spot welds. I then used a thin cut-off disc to in an electric end motor to slice the welds.

Next, I carefully (or so I thought) measured the new patch panel and marked out the floor where it would be cut out. Finding the point where the rear edge of the new piece would meet the old floor was pretty straightforward, and it turned out well. Not so much going up the toeboard, but more on that a little later.

I should add here that I have to replace the inner kick panel, inner to outer cowl piece (the bottom half of the arc-shaped firewall corner) and a small portion of the bottom of the outer cowl piece. I did not want to cut out all of these pieces right out the gate but did remove just enough of them at the front corner, along the toeboard lip, so I could remove the old floor piece and be able to weld in the new one. The second photo shows that area after surgery, and after I had replaced the end of the cab support rail where the parking brake pivot mounts. This was necessary because after cutting away the inner cowl piece that is spot welded to this rail, the end was pretty thin in spots. The area behind the lower door hinge was also cleaned up, treated with rust converter then shot with primer. At this time I also cut out the bad portion of the lower cowl panel and made new pieces from stock I had in the shop. They will go in later.

With the old floor piece out of the way, I cleaned up the underlying supports, treated with rust converter and spot primed. In the case of the U-shaped horizontal support where the cab mounting bolt goes through to the frame, I gave the inside surfaces a liberal coat of paint since this area will get sealed up by the new floor. I then test fit the new floor panel in place and trimmed where needed to get the correct gap at the rear edge, and to get it to sit down over the cab frame rail along the left edge (I notched the lip along the left edge where it goes by the door pillar). Next, I marked the new panel with a paint pen at all the points where it needed to be drilled for plug welding (third photo - sorry about it being a little out of focus. My iPhone is old and has issues like its user).

A note here that the new patch panels are really nice, but as I've read in many forum posts on various sites, they aren't exact matches and do require some tweaking. In the case of the floor pieces I received, the angle of the toe board is much less than the floor in the cab. I suspect this has to do with shipping issues. In any event, once the new panel was laid in place and clamped in, it was clear that I need to bend the toe board upward to meet the firewall. This is where my careful marking of the floor for cutting went awry, as where you bend the new panel changes the length of the toeboard. In this case, the bend caused the new piece to be a little shorter than I would have liked so the gap ended up being about 3/16" along most of the joint, and a little wider in some spots.

The fourth photo shows the new panel clamped into place ready for welding. All of the plug welds and the seam along the rear part of the floor (which will be under the seat riser) went as planned. The last photo shows the gap at the top edge of the toeboard and my first spot welds to connect it to the firewall. To bridge this much of a gap, I have a small piece of 1/8" thick copper sheet that I hold up to the back side of the gap where I need to weld. To get all the way across the seam, I have to weld about half of it from the inside with my arm around the door pillar, and the rest from the outside, lying on the floor with my arm up through the transmission hole. It's a tedious process but it works. My plan is to not have to do this when I install the new piece in the passenger side of the floor.

The left side inner kick panel is next.