To ensure the fit, I cut a pattern out of delrin and made damn sure the thing slid up and down smoothly. After all that, though, I'm building a new bulbless keel with internal ballast. Easy enough to configure on a 5.5 meter sporty, probably not recommended for a 30 :-)
I feel your personal pain. Although mine, weighing a fraction of yours, was a lot less hassle. Still a PITA though. And yeah, the fit going back in is a concern....don't ask me how I know :-)
Hell, I'm going to be an ORG in 2 weeks, (Old Retired Geezer) so should be an email if you need work in the boatyard. I have CF and epoxy and will travel, :-)