DualShock3 with removed battery = wireless?

With a removed battery the DualShock3 would only work while powered by a USB cable.

Will Evo allow this?

No. When you plug in the USB cord before it syncs to the system connected to the cord, it will still sync with the last system that it was plugged into if it is in the vicinity. That will trip the home menu on the previous system. Buy a dual shock 2 and a inpin adaptor from etokki.com.

What about one that’s been fully modded to be wired?

A.K.A. a DualShock shell but with a custom PCB inside.

What about cutting the power lead to the bluetooth module in the controller. Then it would not sync to the previous system. Wouldn’t that fix the wireless syncing problem.

All of these would require someone WAY more knowledgeable on the subject than your average pool judge to even know what you mean, much less be able to verify the changes. If its a SIXAXIS or DualShock3 case, they should dismiss it out of hand.
A good PSX or PS2 pad + converter is way cheaper than the cost of a PS3 new pad, and there’d be no concern or confusion for the tournament operators.

How? Whenever I went to the Break with my regular DS3 controller, Id just plug it into the PS3 and it would sync up in seconds without interrupting the previous console that I was on. And there’s like 8 PS3s all on the same table so I know I couldnt have been too far from it.