I just replaced my rear air suspension air units not because they were leaking but the shocks had gone.
Car rear bouncing about all over the place. This is why the guy sold it ..he had just spent big on the front suspension and I guess though sod it.
The right hand one is easier to do so start there. Jack up the rear wheel under the shock mount. Axle stand under the chassis then remove the wheel and let it all hang down.
I bought on advice a long 15mm rachet spanner for the inner nut ..waste of money had to use a normal one and it was a pain..20 min to get one nut off .
I noticed an upward dimple in the body above the centre of the shock absorber and it would have been a better idea to remove the carpet ,locate the dimple and use a paper pattern from the top of the new unit to find the location of that back nut ..then drill a 1 inch hole so you can use a socket. That nut is towards the front on the RHS and to the rear on the LHS. The outer two nuts are easy.
I did not remove the end fittings on the air pipe but re used and so far so good. Very little air comes out when you detach the brass fitting.
A small block of wood on top of the trolley jack with a V in it below the bottom of the shock helps lift it into place and a crow bar to align.
Takes about 1 hour if you are organised. Always listen to old people or when they die you will live on in ignorance.
The avatar is a picture of the man with a big cock.
Learned to 4x4 on 100 mile beach and Frazer Island QLD
Dont spend money on old cars you will never get it back

I got the hole idea from my jaguar XK8 where you need to cut a hole in the trunk to access the diff plug.
Evidentially on thr RRS there was an access cut out for the front suspension inner nut but later filled in to support a heat shield .Many just re instate the cut out.

Now drives great ..no creaking or unstable bounce at the rear end and it tracks fine without having to continuously adjust the steering . Always listen to old people or when they die you will live on in ignorance.
The avatar is a picture of the man with a big cock.
Learned to 4x4 on 100 mile beach and Frazer Island QLD
Dont spend money on old cars you will never get it back