Good going Al! Latest is a bit over-exposed, hard to graph successfully at least for me. Got a bit of a result on your spectrum 17 Dec (?), attached. I took one the other night, getting easier as the comet gets brighter (better signal:noise in much shorter exposures).
I took a spectra of the comet last night using my LISA spectrograph. It is at the zenith for me around 11pm so easy to image if the clouds stay away.
Lots of strong lines.