Help needed with planning Outback tour in July

Gretings all My Mrs and I are planning a trip in July During the School holidays first 2 weeks Sydney to Sydney. I don't think we have time to do a good Simpson Crossing but I thought we could tour about a bit any way. We will have 5 or 6 other cars with us.

Here is the starting itinerary.

Sydney to Nyngan 02/07/11
582 km
via Gt Western Hwy & Mitchell Hwy
Refuel: Sydney
(713km next refuel)
Camp: Florida rest area

Nyngan to Milparinka 03/07/11
695 km
via Wilcannia & White Cliffs Depot Glen
Refuel: Cobar
(603km)
Stay: Milparinka

Milparinka to Innamincka 04/07/11
405 km
via Tibooburra & Strzelecki Track
- Camerons Corner
Refuel: Tibooburra
(366km) 7d 7-9pm
Stay: Cooper Ck

Innamincka Area 05/07/11
- B&W Graves
- Dig Tree
Refuel: Innamincka
(512km) 7d 7-7pm
Stay: Cooper Ck

Innamincka to Birdsville 06/07/11
512 km
via Betoota
- Haddons Corner
- Waddi Trees
Refuel: Birdsville
(553km) 7d 6-6pm
Stay: ???

Birdsville to Poppels Cnr 07/07/11
175 km
via QAA Line
- Big Red

That puts us about halfway into the trip. I'm still working on the return portion
Iam thinking about from Poppels cnr south on the K1 line 87 kilometers then west on the Rig Road 108 kilometers north on Knolls track for 43 kilometers and then east on the French line back to Poppels crn for 77kilometers. for a 315 kilometer loop. This plus 175 Kilometers from Birdsville each way is a total of 565 kilometers in the Desert between fuel stops both at Birdsville. Has any one else done this loop and thoughts about it? and or return ideas to Sydney?

Thank you.

Ruth and Chris