Re: Volume/treble bleed pot for single P90 guitar
Yes. It is possible to wire things in the way you describe. I almost did that mod myself but thought better of it.
The disadvantage of sharing volume and tone duties on one pot is that whichever function is not using the pot's resistance track will, by definition, be operating at maximum.
Hence, if you engage tone pot mode, your volume setting leaps to maximum. This will be a drag.
Most players of single P90 mahogany electric guitars constantly adjust the volume pot to alter the degree of overdrive from their valve (tube) amplifiers. In my opinion, the volume function should have priority at all times. Your "either/or" circuit forces you to choose between the two.
Personally, on a single P90 mahogany guitar, I only really use the tone pot in two positions: fully up and fully wound down. i.e Normal and "woman tone". I achieved these options by wiring a push-pull pot to act as a switchable treble cut. (See my earlier posting on this subject.)
As for push-pull pot suppliers, try Allparts, StewMac, WD Music and countless others. Twenty pounds (thirty USD) should cover a push-pull pot, a Sprague capacitor and shipping costs.
