Thread: 285/50R20 fit in spare wheel well in L320?

I have recently acquired a 2008 RRS TDV8, very different from my petrol D1 that is now relegated to farm duties.
The vehicle has 20 inch rims and I am just researching my options to set this up as a tourer, it’s basic duties however will be to tow a horse float; one can only dream.
Currently the vehicle is fitted with 275/45R20 Nitto Grapplers (29.7 inch diameter) that are reasonably quiet and good on road, obviously the sidewalls look a little vulnerable.
I am considering replacing them with a set of Falken Wildpeak AT3W in 285/50R20 which are equivalent to 31.2 inch diameter.
I have seen in AULRO threads that the 265/65R18 which is equivalent to 31.6 inch diameter, will fit in the spare well if deflated and can fit when tread has been reduced through wear (I am only using this as an example of wheel diameter).
I have 2 questions:-
Does anyone know if this tyre will fit?
Does anyone have experience with the AT3W with regard sidewall strength; they are 116H.
Apologies for the long winded first thread in 5 or 6 years.
Lee

yeah thats why i mentioned brakes, they will be able to give the best answer,

but as far as i can tell this is the ok smaller brakes

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and this is the bigger style

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