The Build and Finished Product
Unless you are looking to replace the pair of 120mm fan supplied in the front of the chassis there is no real need to be behind here. Releasing seven clips is all it takes and the bezel will come right off leaving the front I/O in place.
I then went to installing the motherboard with the CPU cooler already installed, right on the motherboard tray so when I am ready for it I can drop it right into place and screw it in.
Since you won't get to see this later, I figured now was the perfect time to show you what a longer PSU looks like as far as the room goes. You can see there is just enough room to make the modular connections and still be able to use the back plane of the X-Dock bays.
With just a little thought, the wiring all tucks in between the bays at the front. I have everything connected to the PSU that I need, the X-Dock is powered and SATA cables connected, and the ODD is also ready to go.
With the optical drive in place it doesn't destroy the look of the HAF XB, and since the storage bays have full covers there is nothing to see of the SSD in the top bay.
Peeking in the left side once everything was installed, you can see there's plenty of room for the HIS Radeon HD 7950 video card on the top level, and loads of extra room at the bottom since I removed the 2.5" drive bays rack. Also just by moving the GPU power leads one could easily slide in a radiator at the right end of it behind the 120mm fans.
In the back the rear I/O dust shield popped right into place, and once you have the motherboard tray back in the chassis, the GPU falls right into place and is securely held with the thumbscrews.