There are three or four pins on the Kl25z labeled gnd, I assume those are all electrical earth gnds and not just a common? If they are earth gnd I want them on the same ground buss as the line power right? I plan on getting a metal buss just like that which is installed in a house breaker panel and tying all metal, external power supply, and input power earth gnd to this.
This whole "ground" vs "common" thing is really confusing. And it's a double-bluff kind of confusing...
In general, the "ground" in a DC logic circuit (like the KL25Z) isn't a true Earth ground. The EEs use the term "ground" in a DC context to mean a zero-volts reference point, not an actual Earth ground. So you're exactly right in suspecting that all of the "ground" pins on the KL25Z should really be labeled "common" instead.
However... ATX power supplies are required, by the official spec, to reference 0V DC to the Earth ground on the AC side. If you get out your voltmeter and do a little continuity testing (with all of the power unplugged, of course!), you'll find that there's a hard connection between the ground prong on the AC plug and all of the black wires in all of the PC connectors. And between all of those and the metal case as well. If you open up the case and trace the circuitry, you'll find that the 0V DC side is hard-wired to the AC ground. This is all intentional, by design, and required by the spec for anything parading itself as an ATX PSU. So whenever you're in a PC context, "ground" and "common" and "0V DC" actually *do* turn out to be the same thing, despite the general rule above that it's not necessarily so.
And because the KL2Z connects to the PC via USB, it's automatically forced into that 0V DC == Earth ground scheme by the USB wiring. One of the wires inside the USB cable is a 0V DC connection directly to the black wire from the power supply, so as soon as you plug the KL25Z into USB, you've established a hard connection between the KL25Z ground pins and the ATX power supply 0V DC, which in turn connects it to your AC ground prong via the internal ATX power supply wiring.
So, to summarize: DC "ground" in general doesn't mean Earth ground, but when an ATX power supply is in the picture, it does.
To put yet another surprise reversal on this, you still shouldn't use the KL25Z ground pins as your Earth grounds for the purposes of safety grounding. Wire your safety/ESD ground directly to the AC power plug ground, or as close as you can comfortably get (modulo your tolerance for stripping wires from AC power cables and that sort of thing). The static discharges that we want to protect everything from can be very high voltage, like hundreds of volts. (They're low amperage/low power, but high voltage.) You don't want those voltage levels anywhere near the KL25Z or your PC motherboard or anything else with a transistor or IC chip in it, since those little silicon parts tend to be sensitive to voltage potentials (which is what makes ESD such a hazard to semiconductors in the first place). For your external metal grounding, you want to route all of that charge physically away from the electronics. Yes, it all ends up connecting together when it hits the insides of the ATX power supply, but there are capacitors in there that will help block surges from flowing back into the logic wiring.
So in other words, don't connect the KL25Z grounds to the grounding strap for the external metal.
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