That's probably what I'll do, Coz, or some variation on that. I may even use the piece that was cut out to make a big rectangular cleat. The back has a very slight curvature, so I need the patch to bend and conform to it. It's thin enough that it should with no trouble.
The shop thread is just my outlet, guys. I've been off work all Summer on rehab from this operation. And when I do go back I'll basically be running the clock out, using up leave time and maybe training one last class of Operators. I am giving some thought to turning my shop into a part-time job after I leave public service next year, just to offset the cost of hc insurance. I think it works out mathematically, with the steady flow I'm getting. I wanted to test myself this Summer to see if I had the discipline to do it, 4-5 days a week, but not 7, and not 8-10 hrs/day. I try to limit myself to 3-4 hours at a time. And it's a daily challenge to get better at things, try to outsmart some of these crazy jobs. It's also been educational trying to figure out the economic side. Always before, the shop was my little side-hustle for when I had time, and I could just make up a number that covered my bottom line and fixed somebody's stuff. Now I need to actually make something.
This Martin for instance; this guitar could be replaced for about $750 new. My bill has to be something negotiable between that, and reality. I'll have about 4-6 hours in it, and supplies, plus a set of strings. My customer will have a playable guitar that was a Christmas gift 23 years ago. What's that worth to them? I've never been comfortable putting a value on that, but I have had to start putting some to my time. It's harder than I thought, but I'm getting it. I'm starting to realize that most people, (this guy, for example) are really glad to have their stuff fixed.
*Before I quit yesterday evening, I glued one end of the loose X-brace... got to use my Stew-Mac brace jack. (guitar is topside-down in the picture)