bigruckus, Unfortunately, the three permits is going to get you three parking passes. If you all want and need to start together at 3 AM, then hiring a shuttle would work, but only for the number of people that shuttle can carry.
Since you have some in the party camping, they could be dropped off at Whitney Portal where they can camp by the trail head, and people staying in the motel could then use their car(s), driving them down to Lone Pine, and coming back up next morning.
Just a note about descending in the cars: Be SURE to use lower gears -- even with the automatic transmissions (use First and Second gear!) to keep the speed down without burning out your brakes!
Another option: Each driver reserve their own independent permit. As I write this, there are day hike permits available online for both 7/25 and 7/28. If you watch the online system, people do cancel or return slots occasionally, so for the cost of a single permit, the drivers can get a parking pass. (If they can reserve a permit, be sure their originally reserved slot is returned from the original reservation.)
