I got too much battery

I have a 5.11 Man Pack I use out in the farm when I am out all day, holds a lot and just tosses over the shoulder, holds too much I just found out when I packed it!
I don't have a bottle of water in it yet but the GMRS, Pro-106,DV Corder, 2 tapes 3 video batteries, 2 set's of scanner batteries, 2 set's of AA's for the mini Nikon, 1 pack for my DSLR Cannon, 4 CF Cards and 3 SD Cards, and a small L11 Nikon plus a laminated frequency sheet, Pro-106 manual, a micro-mini leatherman, and a couple of sharpies along with a spiral bound index card book in case we come accross any drivers. I got even more AA's but I think I need to actually re-think my batteries and leave some behind, they actually weigh a ton in this typel of quantity.
The wife will have a backpack with rain coats, a towel, her scanner and 2 sets of racing headsets, binoculars and my son will wear ear-buds with my shooting muffs that she has. Some sun block, Aleve, Pepto pills and a couple of bandannas. I got a few large and small zip lock bags in there too in case the sky opens up to keep the electronics dry and I sprayed the packs and our sneakers with CampDry. He will have a camelback and a set of mini binoculars. I think we have all we need for a 20 hour day but it's going to get heavy beyond the 6th or so hour!
All of this may be overkill but volume wise it's packed really small, I am heavy in my small pack due to batteries and she has a bit more bulk but no weight. I believe in Proper Prepairedness Prevents Piss Poor Preformance!
I got Viper and Cabarius in there for AFTER the race, it may help us getting out or it may just make things worse knowing what is up ahead!
I think our best bet is to park between turn 3 and 4 near the Country Crock camping area then take Pitts School Rd to Roberta Rd then over to 49 and then take that all the way to 49 and 85 or 49 for 485 South. Hopefully we will have options (doubt it since they tell you which way to turn) but the scanner may help. I was planning on parking next to Sam Bass and taking Morehead to 49 but figured it will be too long of a walk from our seats on the front strech to the truck and 1/2 of the place will be on the road by the time we even get to our truck.
This time is a lot of planning and questions, October and there on will be a lot easier and enjoyable since we know what to expect and hopefully what to and not to do.