I've seen this mod done a couple times now and I thought I'd try it out for myself. With the green lighting my red case looks always like Christmas.
1.5 mm & 2 mm allan wrench
Phillips screw driver #0 (preferably magnetic tip)
400-600 grit sand paper
So I started disassembling the shroud. Til I had a pile of tiny screws. I removed all the screws holding the shroud on. NONE on the PCB itself. I did have to remove a couple on the metal bracket that houses the video output ports in order to get the shroud off.
The geforce logo will just push right out of the shroud. I sanded it down until all of the green was gone and it was grayish clearish color.
I then reinstalled the shroud and plugged all the screws back where they went.
The final product...
I'm pretty happy with how it turned out.