I happen to suspect a full shred may possibly be a C5 will hex screws for various reasons.
Another interesting topic, I happen to suspect that alot of Duncans share the same coils except a few pickups, the Pearly gates, Scremin demon, dimebucker, and there may be another I am leaving out. What do all of these pickups have in common? The price!(about $90 a pop compared to $70 or so) They are all unique unto themselves also. They without a doubt do not share coils with any other pickup. Makes me think.
Look at all the neck pickups. Most of them are in the 7.5 range. The Jazz, APH, full shred, Invader and again there may be one or two I am leaving out. Its kind of hard for me to belive they are all completly different coils. Again, unique coils probally cost a bit more to produce as opposed to mass produced coils. Makes me think even more.
The only pickup that dosent fit those theorys is the Distortion neck. Interesting?