#1
I apologize if this isn't the right thread. Im looking at buying the DiMarzio crunch lab and liquifire pickup set..
http://www.musiciansfriend.com/accessories/dimarzio-john-petrucci-pickup-set

You have the option of getting em for the 42mm or 43mm nut.

Ive got a Sterling AX40 guitar ...http://www.sterlingbymusicman.com/ax-guitars
It says the nut width is 41.5mm Nut Width (1.63″, does that mean the 42 wont work?
#3
All that's refering to is normal spacing/F spacing. I have no idea why it's listed as nut width. Your nut width won't affect the pickup.

Either one will work perfectly fine. I guess I'd recommend the 42 though, since the bridge spacing on that guitar is probably a little narrower than normal.
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