|Pro tip: connect the wires and make sure it works before you drill any holes.|
|The bottom plate (with old paint showing around the edges)|
Once I realized the upper plate was going to have to be roughly above the lower one, I drilled a third set of holes and tried lowering the cable from above. I hit what appeared to be a *horizontal* board in the way inside the wall. Exhausted, I packed up my tools and gave up. That was January. On Sunday I picked it back up again, and realized that (a) the horizontal board didn't block off the whole interior of the wall, and (b) the wall was insulated.
|The top plate, with extra holes I had to patch|