Removing I/O Shield ??

Solution
No, you must remove the whole motherboard as it holds the I/O shield in place.

If the motherboard is not yet installed, yes just press from the outside and it will pop into the case.
Damn, I must be tired...
Do people actually need to be told to remove the mobo before removing the I/O shield?

It`s like someone asking: I parked my car in a closed garage. Can I get it out?
A: Yes - just reverse!

Result: BAM!! - reverse straight through the garage door!

Sorry, I`m not trying to be a bad guy by any means. This just didn`t hit me at the moment of posting 😀