I completely replaced all my airbags on my drive and refurbished the EAS system. There are plenty of tutorials here and the other 2 classic RR sites, it isn't difficult, just take your time and to one job at a time. Don't buy the cheap crap o ring kits for the EAS block - you'll regret it, I did.
Mine will go from normal height to max in around 3 seconds now - it took a long, long time to rise when I bought the car (all worn out).
The one specialist tool I needed was hook, wire coat hanger, home made x 1 (bend a hook at one end and a loop for a karabiner at the other) You'll need this tool to yank the rusty pins out of the top of the airbags (rear I think).
Easy test for EAS (if you don't already know) - I put mine on high then press the button to lock the EAS (the one that looks like a flat tyre to the right of the suspension height button. Leave it over night or for 3 - 5 days. You'll soon see which one has or hasn't got a leak as that corner will drop.
Not sure if they all do this but when I stop at traffic lights and keep my foot on the brake (no hand brake or parking brake) the car doesn't really move. If I put the car in park whilst waiting at a red light after around 10 seconds it will start self levelling. These days I worry if it doesn't hahaha.
Hope that's of use to you