Cutting a Truss Rod Slot

It's time to cut the truss rod slot, because the back of the neck is still flat and the face of the neck is just about ready for the fingerboard.  Next I think I have to thickness the back of the "thin part" of the neck down to 3/4", but leave the headstock material there, and once I do that, things will get rough in Flatworld. Once I do this, I'll never be able to lay the neck flat again easily:

The next operation after that will involve gluing on the fingerboard, profiling the back of the neck (into an approximate "C" shape) or both, and the neck will start getting lumpy, bumpy, rounded and so forth.

I had trouble routing this laminate before (see here), but I think that was because I took too much at a time.  I've successfully routed into and through epoxy layers in my thicknessing operations, leading me to believe that if I go slow I won't start any fires.  So I made a setup to guide the router:

I got the correct 7/32" router bit at Ring's End.  I checked the aluminum for straightness.  I took into account that my router base has a radius of slightly less than 3" (2 63/64" or so).  I measured with a metal ruler that goes down to 64ths.  As my grandfather never would have said, "measure 2,028,887 times, cut 2300 times."  I tried to always keep the router pinned to the guide, but without pushing hard enough to risk moving the guide itself.  I cut in small increments, about five passes.  And still I screwed it up!  

Excellent.

That's the truss rod, laying next to its future home.  I created two problems, both recoverable:

1. The slot is about 1/64th to the right of where it should be.  This is due to me being a poor craftsman and a bad judge of distances.   But I've haven't filed the neck to its final width, and I have that much room over on the right if I want it.
2. I goofed up twice and the bit cut toward me in two spots.  Not too terrible; I think it's visible in the image.  I'm going to hide that under the fingerboard.  This happened because I was trying to push back hard, but not too hard, while moving the router left, but not too quickly, while also thinking about how horrible it would be if I screwed up.

Whew.