How do I build a PC Into a Mac PPC G5 case?

How can I convert my (unfortunately) obsolete Mac G5 PPC case into a PC? It only supports Leopard OS-wise and I'd like to keep the beautiful Mac Case and reuse it with PC components inside.

Can that be done? Can the hardware inside be replaced with a PC motherboard etc?

Yes it is possible, and instructions are probably outside the scope of this forum due to the extreme variations and nature of the hardware available.

But heres a video of one guy's journey to turning a G5 case into a hackintosh so you can see what is involved before you make the decision.

And another more detailed tale here again not for the faint of heart.