Hey guys, Ive just got a quick question on swapping out my edge III for a gotoh OFR. I know its a drop in replacement and everything, and I know I may need to route the trem cavity just a tad bit. I was wondering though, it comes with a string retainer bar. Is there any specific spot to screw that in on the headstock? Like, does it have to be .25 inches away from the nut, or anything specifically? Thanks!
I'm guessing you're affixing this string retainer to an Ibanez? Your profile only shows a Dean Explorer and a Stratocaster. I believe the Edge series is an LFR used by Ibanez.

Anywho, check out this Charvel pic:

There are actually two screws that drill straight down into the headstock. That's so it can be affixed to almost any guitar. You're going to want to check to make sure they're not int he way of your strings, however.

The only time I've encountered these are on old Strats and Kramers. I don't see why isn't not easily applicable to your guitar. My question is, however, if you already have a locking nut, then why do you even need it?
Well I swapped out my stock jackson trem for one a couple of years ago and didn't worry about putting the string retainer in and its been fine.

Its not exactly the key part of the system, I'd probably just leave whatever string retention there is in place already and that'll be fine. As long as you're not mixing chrome with black or something