I can finally confirm that the Adjust-o-matic bridge is in fact F-spaced. I did a load of work on a friend's Dearmond M-75 a few weeks back. Dearmond are like the Guild equivalent of Squier for those who don't know, and Fender bought Guild out some time ago, as such parts between the companies are now standardised, so Guilds, Gretches and hardtail Fender models all use the Adjust-o-matic. I took the opportunity to measure the spacing. 52mm. F-spaced. Booyah. 😉