Installed new coil, now the tach acts funny

I did what @67Dart273 suggested and rigged a small gauge wire to the bare terminal on the harness end of the distributor connection, then connected the tach to that. Also corrected the capacitor wiring so that it's wired on the + terminal. Same problem, tach works but only reads above ~1000 or so. Anything below 1000 it reads zero. Since it worked fine prior to swapping coils, and since it now won't work with the old coil, I'm starting to think that @4spdragtop was right and that I'd buggered it somehow with the new coil.

Ordered a replacement, let's see what happens.