About Commodore, they had indeed plenty of small variations among models and it's been a pain to sort them out. It could well be that a few of the duplicate sets will be removed later, if there was really no difference between them. However, if you find any mistake please report it, I could have easily overlooked or misunderstood some of the sources.
I already organized them when I rewrote all of the 8-bits. The PET line has different memory sizes and 50/60 Hz video based on region.