After a few more passes with the chisel, her neck slipped smoothly into her body, and things were starting to come together. I put a clamp on the joint to get a closer look, and was pleased at how tight the fit was where her neck heel meets her body.
Next, I placed a piezoelectric pickup and a new saddle in her bridge slot so I could check her action and neck-to-body center line alignment. With some fishing line in place of the high and low E-strings, I saw just how little work I had left to do on the dovetail joint and took care of some of it with sandpaper.
Although the neck joint was not perfect, it was close enough to drill out the neck heel and block to receive the nut insert and bolt. I worked on her neck heel first, and laid out work lines to locate the hole.
Lacking a drill press in the This Old Guitar workshop, I used some clamps to hold her neck flat and steady to the work surface. After setting up firring strips to get the vertical alignment, I used two hands to guide my variable speed drill. I worked my way up with three drill bits and a slow drill speed to keep the final hole aligned with the pilot hole, and managed to get the insert right where I wanted it to be.
With a few turns of an Allen wrench, the insert installation was complete.
Moving on to the neck block, I located and marked the spot that had to be drilled out for the matching thru-bolt. With a long straight edge, a few more firring strips and some painters tape to hold everything in place, I was ready to drill the hole.
The hole is so close to the top of the block, it's really more of a groove that receives the bolt.
After cleaning up the edges of the groove with a file, I realized I'd have to trim the top brace just behind the neck joint to allow a 11mm socket and driver to sit properly on the nut end and be able to turn it. That was easily done from the inside of her body with a Dremel.
Since everything is such a tight fit, I also had to trim some material off at the base of the neck as well as trim the washer that distributes the compression force into the neck block.
Before a trial fit up with a set of strings, I made a run down to my local Guitar Center for a pair of black strap buttons and a set of bridge pins. After dinner and before going to the pool that night, I put on a fresh set of D'Addario EJ15 strings. It was great to hear some music come out of This Old Guitar, and she sounded surprisingly loud and clear. With that, I pulled the trigger on ordering a replacement preamp unit through eBay. The preamp is coming from China, so it will be a few more days until I have it and can install it in her existing body cavity. Just as well, my shed is still too hot of a place to be, thanks to the current heatwave we're experiencing here in North Carolina. That also gives me some time to make some minor finish repairs to her neck and fretboard binding that suffered some collateral damage from my chisel, as well as to add something to the neck block that will retain the bolt from slipping within the groove. Until then, she's sitting patiently inside the This Old Guitar shed.