Last I checked, the M-box definition available on your SVN was very far from "all the maps".
That'd take a ridiculous amount of time to do by hand (4000+ maps/constants).

It's not hard at all to find everything that is needed to tune, at least for me... it's just tedious.

Oh, I agree...
But there is so much that can be automated.

I played around with some algorithms, and I am getting pretty good results with just binary analysis.
An amalgamation of my map pack parser and XDF generator.

Obviously some things will have to be done by hand, but I should get a pretty good file by just feeding it existing things.

The algorithm searches for all the maps with the exact same contents within a 50kb offset, with some limits (minimum map size).
After that, it takes each match, and sees how many bytes in front and behind it match as well (outside of the current map area).
It then chooses the map with the largest matching region, which pretty confidently is the correct thing.

Once you have a few key maps, you can then do the same region extending technique, but lift the minimum map size limit, thus getting lots and lots of things.
There's a few quirks I have to sort out, such as locating axes, but other than that I'm almost done.

Just flash with 551K in boot mode. 551F and 551K are incompatible between each other indeed...

You should be able to get it into boot mode regardless of what is flashed onto that chip.

You could flash complete crap onto that chip, and you'll still get it into boot mode.