We've got heaps of orphan sides and backs (inevitable if you do any re-sawing) which are all uke size and we also use one piece neck blanks for our guitar necks so there's always a big lump left in the middle. These now get turned into Mando or Uke necks.
Here's a few pics.
Note the forward shifted, hemi-parabolically scalloped pre-war inspired bracing.

Highly customised glueing jig.


I found the plans for this on Christophe Grellier's website. They are free and there are also plans in .PDF and .DXF format for an OM, OO and L-OO
and very nicely drawn.
The link is here.
http://www.grellier.fr/plans.php?lang=en