Size of screw GB14X#MT10B for 2-6-6-2 Mallet

[paultorrey]

Dear Bachmann,

I'm  hoping that someone can help me with the actual screw size for this hex headed screw that holds the side rods on the drivers for a Large Scale Mallet 2-6-6-2.  It's Bachmann part number GB14X#MT10B.  I've snapped the head off a few and need to drill out and tap the screw hole.

Your help is appreciated.

Thanks,

Paul Torrey