I clamped the infill into the plane, clamped the plane in the cradle, squared the sole to the drill press table, and drilled the first hole. And if the original hole had been oriented this way, things would have gone better. (No, I didn't check.)
In the picture, part of the problem is pretty obvious: the holes don't line up on the exit side. What's not obvious is that because the bit didn't squarely engage the inside of the second hole, it shook a few things up, and the infill shifted in the shell during the procedure. So the hole through the infill was not as clean as it should have been, and when the pin was inserted in the resulting hole, it pushed the infill up, and out of alignment with the shell. I had to file the hole in the shell a little bit, and file the hole through the infill a lot. What eventually I figured out that setting up the iron would help. The lever cap clamps the iron down to the infill... and clamps the infill down, in this case, to the shell. So I did that, and chased the hole with a cordless drill. I had to insert some bits of wood into the infill to patch the hole and get everything to line up, but the end result worked fine.
I have to admit, it was hard not to succumb to the 'Oh, no, all is lost,' feeling that I had in the moment. But it helped knowing that the plane was not immaculate to begin with, and to know that a repair was (almost) always possible.
Setting up the iron was a minor issue. The patch for the handle shifted its position a little bit, and the iron came to rest on the end of the handle, instead of the bed, so I needed to reshape the handle.
For the second pin, I did everything with a cordless drill; drilled into the shell, chased the hole through the infill, and drilled back out. Much easier.
Peining the pins wasn't too hard. It would have been easier if I had a real anvil, or big block of steel to work on... maybe a chunk of railroad track or something. But no, all I had was this cocked-up wad of self-delusion. --->
It worked, for which I'm grateful. But a 4 lb hammer clamped to the bench is not an anvil. I'm gonna have to find myself an anvil, or some old, abandoned railroad track if I'm gonna keep doing this kind of thing.
I should have taken more pictures of the peining process, but truth be told, it was pretty nerve wracking, and I was more worried about getting my favorite plane back to normal than I was about sharing the
After everything was put back together, I had to give the plane a good going-over. One side of the bed, despite my best efforts, was still a little bit high. And all of the peining had distorted the sole by a thou or two... enough to prevent me from getting a good, full width shaving at the finer settings. But these weren't too hard to remedy. I may still need to tweak the plane a bit here and there, and I do need to touch up the finish. But it's done, and it works.
The whole re-assembly made me feel like a rank beginner... which was uncomfortable. But I AM a rank beginner when it comes to this kind of work. The point of the project was to get the handle solidly re-attached to the rear infill, and the handle feels solid now. And the plane still works. So even if it wasn't what I consider an expert repair, it was successful. Considering that I regularly use this plane, and don't need a conservation-level repair, that's good enough for this go around.