Best I can tell they've been developed for the diesel truck market. The bell housing mount pattern isn't the same as the ATI or Reid bells, they'll be offering their own bell housings as well. I know nothing about the particulars of Cummings diesels, I have no idea what the bell housing pattern is, so you might be waiting a while to see something that fits your SB or BB. Hopefully they offer something that takes the aftermarket bells we have already.