Running dual CPUs

[Gerard Samuel]

I acquired a pair of Slot 1 CPUs that is supposedly a matched pair.
I've heard, that they must be of the same stepping, and Im not sure of what Im 
looking for.
CPU specs are at ->
http://processorfinder.intel.com/scripts/
details.asp?sSpec=SL3XL&ProcFam=25&PkgType=ALL&SysBusSpd=ALL&CorSpd=5775
Just trying to be careful before I fry the thing, so any pointers are welcome.
Thanks