Thanks for the replies.
It is 15 years old yes, I've had it ten of those so unsure whether the key issue has been fixed, I will look in to after I've managed to fix the acceleration issue. I've checked the boot space and there is no damp in there, as mentioned it never goes out in the rain so it looks like it survived its 3 months outdoors in that relation.
There is no panic button on my key fobs, I have three two plus a service fob, not sure if these are different to the American and European spec?



You have got me with the diff oil, done a full brake fluid change whilst I was waiting for parts, gearbox filter and oil, after buying a long dip stick paying stupid money for a tiny locking pin, even the screen wash has been flushed and replaced, only by chance though as when it was serviced the garage said there was a leak, so I stripped it all out and found it was only leaking from the filler neck joint, the system was already full when they tried to fill it more!
You have me on the steering fluid also, something else to do whilst its off the road.
I can actually get a RCM Chrysler Crossfire parts and accessories parts are difficult to come by for the SRT6, Ebay suppliers just supply parts for the normally aspirated versions and believe them to be the same, motor factors don't stock parts specific to the SRT6/AMG32, a lot of parts you need to source from the Mercedees dealers and to be honest, they are not interest in anything Chrysler, there is a certain stigma when you say Chrysler in the UK. I did put a new serpentine belt on when I changed the water pump and alternator, again I had to get this from the dealers who assured me Mercedees parts don't fit Chrysler's.
Regarding fluids, believe it or not, Amazon are the best place to source fluids, they have a wide selection of Liqui Moly products, better than anywhere else.
I'm looking at the new fuel filter and old fuel pump now as a possible issue so I may as well reference and source the oil for the diff and do that at the same time, looks a quick task also, steering fluid will have to wait another month or so.