You have never heard the line, "Yes Virginia, there IS a Santa Claus!" ??? If you give a crap, you can google it.
As for the LED Back light drivers, they are on either the power supply board, (Very common) or possibly the main board, (less common).
Sometimes they do have their own board. (not in your case)
This brings me to a point, As you can imagine, it can be very helpful to see a picture(s) of the back of your TV, so I can direct you better, and get a better feel for what
is there that you are working on as all TV's are built differently.
"
1) plug tv cable into TV, then plug the cable into the mains wall socket, then turn mains switch to off, most important part lol, then clip my wrist strap to the metal chassis, then I should be all good and grounded hopefully do you agree. "
That's overly complicated.
You can do those in any order. Also the power to the TV is NEVER
not connected, (unless unplugged) because the switch does not cut the AC power going to the inside of the TV, (It's a sleep button) When you have a remote control to turn on the TV, the TV must have power, so it's "eye" can see the light from the remote, and then take the processor out of sleep mode, and turn on the backlights. So whether the TV is powered up or not, it is connected to, and using 110Vac.
That said, the chassis is supposed to be connected to the neutral side of the outlet, which in actuality, In the Fusebox,--- ground and neutral are connected to the SAME grounding buss, that connects to a water main, which is in the real earth GROUND dirt. And if your house is wired right, the bigger pin on the outlet is at the same potential as the ground pin.. But for safety sake we connect to the ground pin anyway. USUALLY the outlet box screw is also connected to the same ground pin. So we connect to that for the wrist strap. The chassis metal frame should have a ground wire connected, as well as your wrist strap to that screw.
Put more simply, Two ground wires, one to the TV chassis, one wire to your wrist strap, but that one has a 1 Meg ohm resistor in series to the ground screw. I won't explain why, but it IS important though.
If there was a wiring error, there would be a BIG spark when you clip the ground lead to the chassis, when the TV is plugged in. If there is no big flash, your safe to connect yourself to ground, even when the TV is plugged in. And it's safe to grab the metal frame. But most work is done with the TV unplugged, unless you need it on for troubleshooting a live TV. And this I do all the time.
Whether the TV is plugged in or not, the chassis and you need to be connected to ground. And you can safely replace circuit boards with no static damage.
__
"1) plug tv cable into TV, then plug the cable into the mains wall socket, then turn mains switch to off, most important part lol, then clip my wrist strap to the metal chassis, then I should be all good and grounded hopefully do you agree. "
NO!
The mains switch is NEVER OFF. (Unless you mean main at the fusebox, and that is unnecessary.)
So NO, I do not agree with this, as when you are replacing parts, (Your TCON board) there are still voltages ON in the TV. It must remain unplugged when changing boards.
I apologize if I am man-splaining, I just want you to keep your oxygen addiction, and your TV alive too.
Last part, I don't judge, I would have gotten the TV too! It WAS the TCON only, before somebody messed it up a bit more. If only we knew who?
Yeah, I think the connector is dry by now. It can't hurt to warm it up with the hair dryer ON LOW, or don't get too close.
And lastly I appreciate your consideration for the work I have put in to help. Work slowly, and think things out before each move.
If a question pops up, feel free to ask, I will keep my eyes on this thread.
Your welcome! And good luck!