Maybe one of these ?

https://www.fullfatrr.com/forum/topic40178.html
https://www.fullfatrr.com/forum/topic58383.html
https://www.fullfatrr.com/forum/topic64721.html
https://www.fullfatrr.com/forum/topic64774.html
https://www.fullfatrr.com/forum/topic63320.html
https://www.fullfatrr.com/forum/topic63172.html

Thanks Alistair, I will try these options, I have a feeling that as it is sat on an incline the gearbox is 'locked' maybe an old skool thought, so will give it a nudge tomorrow with the 405  2013 L405 Autobiography Baltic Blue
2007 L322 Vogue Buckingham Blue

If you ensure the vehicle is secured safely (chock the wheels etc.,) then you should be able to put the box into neutral. I can't remember if it's the same on the 3.6s but I had to do it a couple of winters ago with my 4.4 when I blew up the rear propshaft.

Lift the cup-holders out of the centre-console and there's a little flap you can remove, there's then a red flag / tag that you can pull to put the box into neutral. I have a feeling on the 3.6 which has the 6HP it might be accessed via the side but I might be wrong. Ed