Shoot, that's not so bad.
We're this one mine, and the endgame a restoration to Series I specs, I would first rout those cavities to an exact template, then fill with wood and re-rout for correct size/shape. Then I'd do an inlaid wood pickguard to cover the work.
That's a unique guitar you've got there! And sure enough, the inlay is reminiscent of the Lesh Osage Orange... not exact, but I'd say definitely one influenced the other.
Anyone got a comment on the logo? I've never seen one quite like it.
Thanks for sharing!