Matt Blaze has some excellent photographs of decoder tool and punch tool used to dump the pins in a Best I/C core. You can visit the URL directly by clicking
HERE.
Although I'm not very familar with the process myself, you might try asking grit1 what kind of equipment investment is needed in order to start re-keying I/C cores correctly. I know he's been spending a good deal of time and money on these systems in the past few weeks.
As far as instructions go, you MAY find a kind local locksmith who may go over with the tools and process necessary to do it, although it's somewhat unlikely as they would be potentially losing business were they to do so.
I would go with quickpick's advice though. Usually the investment needed is too high. The few times I needed an I/C rekeyed I just took it to my local lockie and he was able to do it for a very reasonable price.