Ground shielding. Anything else hasn't been tested.
Here's the thing about the OMGWTF. It was designed to be
the trim for the Wii. Cutting less than the OMGWTF can lead to compatibility issues or unknown errors that we might not be able to help you fix.
I'd just try the OMGWTF because it's not as hard as it looks and it's well documented.
If it's money that's an issue, I believe you can OMGWTF and still use the original regs. You'd have to ask
@ShockSlayer because I believe he did test it at one point but I'm not 100% sure.