That is my preferred parking lot, it is less crowded and since it boarders a defense contractors property there is a security guard and off duty PD officer watching the area 24/7.
Green Trails makes a more detailed map of the mountain, it can be purchased at REI at Priest and Southern (about 2 miles from the 46th street trail head)
The park is well used after dark, hiker's and mountain biker's lights can be seen on the trails well past the gate closing time. While some of the developed area's close at 1900... the trails are open until much later (2300 I believe).
If you are staying at the AZ Grand Resort, there is really no reason to drive to the parking lot as the East loop trails run along the golf course and can be accessed easily from the resort.
My engine company is first due to most of this side of the mountain as well as the resort, so if you have more questions about the area let me know.