Well, I was actually thinking about using the parts myself and see if I could find myself a CPU somewhere. As his son, I would assume that I would get first dibs.
In any case, it's not a big issue for him anymore because his employer purchased a brand new iMac for him to use at work so that will suffice for him now until he can afford the replacement Mac. He's even considered a high-end G4 Power Mac mainly because most of his apps are still PPC-based. Regardless of whether he goes with the G4 or the G5, I will most likely end up with the PMG5. Sorry man... :-x