Thanks for the insight and suggestions. Sorry for the slow reply here... finally had some time to get my hands dirty today. Started with 75 VAC on the mains, and just like you guys said, current spiked for a second while degaussing and then just hung out around 0.5 A. Sound came right up, so I dialed up the line voltage and after adjusting VHF tuning - voila, bright white snow. It's ALIVE.
I knew a variac is a must on most pre-'70s audio stuff just due to the filter caps, but wasn't sure how it'd work on an "ancient modern" CRT. Good to know now, and yep, definitely a good exercise to perform. Appreciate the help!