I have owned a Schecter Blackjack EX 6-string Baritone guitar for a few years. Its a decent guitar but I've always been looking for pickups that would give it a more defined sound. I've been reading about the DiMarzio D Activators and it pretty much sounds like what I'm looking for.

I'm unsure if I need to get the F Spacing or standard spacing of these pickups. Or if it even matters for this kind of guitar. I've read the DiMarzio FAQs about this issue and it just seems just confuse me even more. I've tried to measure the nut and the pole pieces of my current pickups, but the measurements never seem to be accurate to what I've read they should be. Any one have any advice?
The nut doesn't matter.

Measure the distance between the middle of the 1st string and the 6th string on top of your bridge pickup's bottom coil. If it's above 50mm, get F spacing. If it's below 50mm, get Regular spacing.

Do the same thing for your neck, measure the distance between the middle of your 1st and 6th string on top of your neck pickup's top coil.
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