Quote Originally Posted by Simon Barden View Post
Note also that you'll really want to get a string retainer bar so a) the strings can be pulled down onto the locking nut, allowing you to use the main tuners to tune up and keep it in tune when locking the strings and b) allow the string locks to simply clamp down on the string to hold it in place, rather than one end of the plate also having to counter string tension trying to pull the plate up. They do clamp a lot better.
I'm by no means an expert here, but I'm not sure if a string retainer bar is really needed here. These headstocks are angled unlike F style headstocks giving the strings a decent break angle behind the nut. None of the Ibanez models I've seen have string retainers. Looking at my Ibanez S670 just now, all strings have the exact same angle behind the nut (except the low E but that's only because it's been wound poorly). Same deal looking at my son's RG and his IB-7 kit build.

I think you'd also have trouble fitting a string retainer with a truss rod cover in place. There's not a lot of real estate around that low E tuner.