I don't know why you are so obsessed with making "bump keys" for Best's SFIC [old] open keyways... You will maybe come across a system that is still using them here and there... The [old] SFIC keyways are often used in retail establishments because they are MUCH cheaper than the new Best restricted cores, and the retail company can source them from more than one supplier... Often times you will find however, that those cores used on retail stores ARE NOT masterkeyed and therefore unless a very poor key bitting was selected you WILL NOT be able to "bump" them...
So right from the word go your little scheme will only be effective on a very small percentage of the SFIC cores that are out there in the realm of locks being used... You have not even considered that you are only focusing only on the one OEM brand of SFIC... There are several out there to choose from:
-- Best [most of the new keyways are factory or dealer restricted only]
-- Medeco KeyMark SFIC [good luck trying to find out how many of those keyways exist]
-- Schlage Everest "B" SFIC keyway family [requires special tools to make keys as they are shoulder-stop SFIC cores rather than tip-stop]
-- Kaba Peaks SFIC [a few "commercial keyways exist, but many are dealer restricted]
-- Arrow [has a few SFIC keyways, bust mostly clones old Best]
There are others that produce SFIC cores that are usually only sold to distributors in the locksmithing industry, as well as many of the OEM hardware manufacturers produce SFICs with [old] Best keyways in order to sell more door hardware to architects and contractors than they would if such people had to purchase the mortise door locks from them and then had to purchase mortise SFIC housings and cores from another company...
Rather than continue to pursue this "quest" for "bump keys" you really should practice and refine your picking skills as they pertain to SFICs... This will help you out in the long run, because you are unlikely to possess a set of "bump keys" comprehensive enough to accomodate every SFIC keyway you will encounter while working out and about in the real world...
Not to mention the FACT [not internet myth or rumor] that you will be wasting an awful lot of time playing with your "bump keys" should you choose to actually produce them and carry them around with you... If you can't pick a SFIC, then just drill it out, because time is money...
Evan, ~~ formerly a maintenance man, now a college student...