Swapping out G5 tower parts with another G5 tower?

I have a 2.0 Ghz Dual PowerPC G5 (3.0), 512 KB (L2), 4GB Ram with a 1Ghz bus (June 2004 model).

Serial # G8438CKYQPR

Is it possible to swap out the ram, video card and hard drive and put it into a 2.0/2.5Ghz Quad PowerPC G5 (Early - Late 2005 Models)?

Want to know if they are compatible before I have this attempted?

Any help or advice would be much appreciated.

Thanks,

BboyTV