This probably isn't what the more advanced hikers would tell you, but if it was me, I would approach it as a "practice hike". Don't see any reason why you can't make it to Trail Camp and enjoy everything the Portal, Whitney, the trails and the people have to share with you. You can check out how the parking, the camping areas, hiker camping area, etc. and just learn what you need to do the next time you go up. Knowing the trail can really help you the next time. You'll know the steepness, the springs and places to get water, the terrain....and you can take your time and enjoy.
Now, by next time, I mean in a couple of months, possibly as late as late September. So you can keep your goal of making it this year. After Labor day, you should be able to "walk in" any day. Just contact the visitors center for available dates. When I went last year, the second week of October after weeks of beautiful weather, there were 96 available permits.
I've only been up a couple of times and summited once, both last year, so the more experienced hikers will be able to help you out a lot more. Seriously though, get Doug's book, learn all you can about the nature of Mt Whitney and the draw of it. When you hike Mt Whitney, it will be one of the most unique and possibly spiritual experiences you will have. And it will be one you will share with others, your family and someday your kids. Good luck!
