Here's one with the components for anyone interested, just to clarify the pot lug connections.

When the volume push/pull is down you have 'parallel mode' with the standard Bridge/Both/Neck on the pickup selector. With the volume push/pull up in 'series mode' it just gives you Bridge + Neck in series, the pickup selector has no effect.

Click image for larger version. 

Name:	P90_phase_para-series_pushpulls_v1.png 
Views:	1639 
Size:	425.6 KB 
ID:	31245