Hey thanks for the quick reply. The distance is 12". Looks like a good true bolt on neck. It's a tune a matic bridge (I think that's what they're called). An adjustment for each string with knurled wheels to raise and lower it, on a wodden bridge. Has a Tremalo tailpiece also. I have a complete Epi 335 I got these parts with about 20 years ago. Been in a box ever since. Just like a novice, I didn't consider the arched top problem! Just normal hand tools, router, dremel, cheapo jig saw. (made a few bird houses haha). Raeady to buy what I need within reason though.