AMoses, that is how you can do it. It is good for someone who doesn't have the right tools. Apple used to make CRT tools, and those were nice. If you can, I'd highly suggest getting a specialized CRT discharge tool, though the act of discharging it (like how AMoses' tool will do) is what matters.

Though the actual tool contains a rubberized handle with a dog clip coming from the handle, which is an extension of the probe. You clip the one end to the metal frame, and then you poke the tip under the rubber cap to make contact.

By the way, if done with proper tools, you NEVER see sparks. In the time that I did pro repair on iMacs, I never saw sparks. That seems a bit dangerous AMoses, and I may suggest investing in one of these tools. It doesn't take much for that high of voltage to jump. Just worried about safety.
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Canon Rebel XTI
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