I think you could infer some info from a traditional 7ender Stratocaster. The traditional body dimensions are 1-3/4" thick, and they rout the neck pocket .594" +/-.020. So, doing some mathz, 1.75" - .594" (with a .020 variance) gives you just over 1" remaining under the neck. Keep in mind, that is also using a neck plate without recessed screws AND that's just what Leo did, doesn't mean it's gospel. Plenty of people will tell you that 7ender bodies have chunky, uncomfortable heels too, AND there's plenty of other guitars out there, including 7ender, who use an angled heel to shave off some bulk too.
All that to say, I'd be removing some material from the neck, 1/2" of body left might be okay, but it gives me pause. Hopefully someone like Bruce, someone much smarter than me, will be along in a bit.
I hope that helps.
Yeah, I did similar figuring based on 7ender dimensions. When I did my initial calculations, I forgot to account for the recessed ferrules; I was ok at 3/4", but as you said, 1/2" gives me pause.
Not too late to make it a set-neck, I suppose!
