Flyback Swap

[karmaman]

I know this isn't really about TV's, but I was hoping I could get everyone's advice on doing an FBT swap for an old iMac I have. It's the first model ever released, quality-built in the US, and they would be near-indestructible if it wasn't for a glaring design flaw: the placement of the FBT. Instead of being placed next to the tube, the chassis is mounted vertically next to the tube and the flyback hangs over the tube, making it run extremely hot. About 3-4 years after the iMac had been released, reports of iMacs with dead FBT's started circulating the internet, and now that these machines are considered vintage, It's a well-known fact that they are notorius for having bad Flybacks (they overheat, the insulation on the wires inside melts, and they short). I've got a Revision A iMac, manufactured September 1998. It's in great shape except for the FBT, after it's been on for 10-30 minutes, the screens starts flickering every few minutes and you hear a quick zap from inside. It bugs me when I use it to know that it's only a matter of time before the FBT completely shorts and the iMac refuses to start up (the classic symptom of a dead FBT). I have found a replacement fly (LG #: 6174Z-1003G) online for $30 and a page with detailed instructions on doing the swap (http://www.macopz.com/columns/imacrepair/) and feel fairly confident about doing the swap, the only part that gets me is discharging the tube. Basically stick an insulated screwdriver under the cap, and make sure the screwdriver is connected to ground, right? When I google it, all I get is idiots saying "zomg teh flyback is very dangerous why risk ur life over sum old computer go buy a new one flybacks can kill u". I know it's not true, but I just wanted to check with the pros. Can you guys tell me how to do it? Also, a lot of websites recommend connecting the screwdriver to the ground pin of the power connector on the iMac itself, so when the CRT discharges all that current goes to the ground on the chassis, and to do it without having the iMac plugged in.... wouldn't that screw everything up? Well anyway if this doesn't belong here, please feel free to delete. Thanks!