The key is to not enter the Class B without an explicit clearance. I would fly northeast bound, climbing to 3,500. Once EAST of the PXR VOR 15 DME (a good visual reference to this would be just as you pass the Granite Reef Dam), I'd keep climbing to but not including 5,000 until receiving a Class B entry clearance from Phoenix Approach. Then and only then after receiving the clearance I would get permission to climb into the Class B.
If you want a local perspective, I'd highly suggest contacting Falcon Field Tower via phone at 480-981-1376 prior to flying the flight. I find it's always best to ask the controller, because you never know when they have a standard operating procedure that deviates from the traditional flight school approach. You can also call Phoenix Approach at 602-306-2500 to inquire if Falcon Field Tower isn't certain.