It's the standard Dingwall 3X pickup arrangement. Don't let the tight spacing fool you into thinking that they're all a lot of the same. On my Super J if I combine neck and bridge, middle and bridge, or neck and middle I get wildly different tones, and the same goes for solo'ing neck, middle, or bridge. I installed a 6-way switch to facilitate these options and it yields an absolute ton of different tones to choose from.
Can you ELI5 how the 3 pickups on the Lee Sklar model are different from each other? The Dingwall site describes 2 pickups, which I think is the previous Lee Sklar model.
