This week we had the opportunity to wire a Largeframe Vespa Allstate to a Vespa VBB/VNB Type Stator with external coil. Before I forget what we did, I thought I'd make up a diagram for anyone in the future who may experience a similar situation.

This is just one way to do it. Since the black wire from the stator is the ground and the white wire on the harness is the ground, you could also replace the black wire on the stator with white and run the yellow stator wire to ground right at the coil. Furthermore you could replace the stator green wire with a yellow wire so everything matches inside the junction box. For those less electrically inclined, just follow this diagram.