Can't remember where it is

Howdy folks nice to see this place is still rolling along. Got a question i cannay figure out. I remember in DS2 and BW that there was a way to increase the autocast limit by getting it to include the reserve spell spots. i remember just editing a file and changing a 4 to a 6 but don't remember what file nor have i found the answers on the web. if anyone recalls how to do this i'd appreciate the info. hope y'all have a lovely day.