Hand drill with odd fitting, marked as M-B Tool Co, Danielson Conn, Pat Oct 30 1917.

I can't find any info on the M-B Tool Co, and what is the adjustable fork fitting on the end for?

More than likely a valve lapping tool. Can we see the whole thing.

Might help to have a picture of the whole thing.

Wood handle and 17 inches long.

it does look like a valve lapper with bolt, you could remove the end and put on one for a different style valve.

many lappers came with 3 or 4 diff. tips.

I can't tell from the picture, but the end tips looks like one that Walden made for the Ford Model-T valves.

Yes valve lapper and i think your right about that particular attachment being for fords turnnut.

 Bill300d,  I just checked my list of tools for my tool boards and the Mossberg 608 is the same, has the long prongs.

my Walden VG2 has short prongs,  same style long handle.   I have the Walden VG3 short stubby handle, also short prongs.

my tools are not mounted yet.   both boards are original Walden & a Mossberg one is 1917 and the other is 1923 and
both were for Ford Model-T tools.   both boards had been stripped of the hooks and left roughed out holes.

I hope to find every tool to fill them before I leave this life.

I wish you good luck in filling those boards. If i come across anything I'll let you know.