I still have the scar on my left hand from an electrical burn that I got when I opened my V4B and stupidly thought it would be easy to "service" it, way back when I was 17 and knew absolutely NOTHING about tube amps (never mind electronics!).
Now, and an EE Tech, even though I've been into a LOT of tube gear, things like the SVT (and some Audio Research hi-fi power amps) still scare me.
Approach with RESPECT and CAUTION, or prepare to die...
I’ve never lost having respect for the potential for harm when dealing with electronics. You can never let you guard down.
As a kid, a soldering iron took a nose dive into my leg. That scar serves as a reminder to not do boneheaded things.