My "new" '74 Duster- or why I need a project like a hole in the head

Ok, time for an update. First, yes, I took a hiatus from FABO back in October and November. Part of that was fire season, I was deployed out on fires a couple times. Part of it was just being sick of all the BS that happens from time to time here. And part of it was because my Dad had cancer. He passed right before Thanksgiving. So frankly I've had a lot going on. Working on my cars has usually been therapeutic for me, and although my projects are definitely in need of some prioritizing and probably some thinning in light of things I have done some stuff with my Duster. During all of this I was running a lot of miles on my Duster and ended up running right into the cords on my tires. Of course my old BFG KDW2's have been discontinued for years, so I had to go looking for new options. I ended up with a set of Falken Azeni's, the front stayed the same (275/35/18) but in the back I went to a taller tire - 295/40/18. Which is great, but I didn't count on them being much wider. Because my 295's are on 18x10's, the taller sidewall allowed them to grow a bit, and I was already pushing my luck on the quarters after my rear disks added 5/16" to the width. So I decided to to a "reverse" mini-tub to take advantage of all the space the factory wheel wells steal away from the nice wide quarters. Not the first one to do this by any means, I've seen a few different takes on it but @fishmarket was my primary inspiration. Anyway, here's the issue-
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With the 295/40/18's there's only like 5/8" from the tread width to the lip, but of course the "bump" in the wheel house means there's really much less than that. It works ok with nothing in the trunk because I have some vertical space and a large rear sway bar, but a trip to Costco and I'll be in real trouble. So the solution looks something like this, making the tub look something like that red line
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Except that blue line indicates the section of C-pillar structure that has to be modified. But first the undercoating has to be removed
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Red line shows the plan for the cut, I'm not going to replace the full outer wheelhouse because I'm doing this right side up on jackstands with the quarters on. So just what I need to get the room for the tires (well, and then some). Factory welding looks good right? C-pillar spots are barely attached in a few spots on the driver's side...
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Drilled the spot welds and did some cutting
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And voila (yes, it was rubbing with suspension travel)
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