Sort of... If you have 2 P90's and one is RWRP then you could wire the two pickups together and it would buck hum but it's not going to sound like a humbucker because the bobbin is a different shap. To wire the pickups like a humbucker simpliy wire the hot of one pickup to the hot lug on your switch or pot and then wire the ground of that pickup to the hot of the other pickup. Then solder the ground of the second pickup to the guitar ground.
Not taking any online orders.
If you want a humbucking P-90, DiMarzio makes one, and I believe Seymour Duncan has the P-Rails, which is a P-90 and a rail SC in humbucker form that can be split for either of the SC voicings..
Then there's this band called Slice The Cake...

Bunch of faggots putting random riffs together and calling it "progressive" deathcore.
Stupid name.
Probably picked "for teh lulz"

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