I often drive around The New Forest and many other places looking for a shooting opportunity and leave my camera on the back seat of the car "ready to go".
I have purchased a "Car Tidy" from Amazon that was designed for kids "junk" and found that it will hold a 5D3/7D2 with a EF 100-400 MK II attached in relative safety as it will not roll or slide off the seat, for £12.99 I think it is value for money.
Item can be found at https://www.amazon.co.uk/gp/product/B01GV6YG1K/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1
Hope this of use to someone.
I have purchased a "Car Tidy" from Amazon that was designed for kids "junk" and found that it will hold a 5D3/7D2 with a EF 100-400 MK II attached in relative safety as it will not roll or slide off the seat, for £12.99 I think it is value for money.
Item can be found at https://www.amazon.co.uk/gp/product/B01GV6YG1K/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1
Hope this of use to someone.