9" drum hub drill to BBP?

People have enough concern drilling drum rear axles to install BBP studs. I haven't heard of anyone wanting to install BBP studs in a front hub. Usually, they go BBP because they changed to 73+ disk hubs (thus need to BBP the rear). I don't know that 9" drum hubs have a smaller diameter where the studs sit than 10" drum hubs. They do use smaller wheel bearings.