Thread here for servicing/tuning RL2, should be some relevant info. to get you started at least.
https://forums.mtbr.com/shocks-suspension/official-xfusion-rl2-fork-service-tuning-thread-910996.html
Just done lower leg service on my sweeps, no need to get the special tool but you need to be gentle with those “cheesy” nuts as said!
Fox 34 SKF seal kit for mine and Stendec 7.5w (Chainreaction) for oil.
I think it might be same weight oil used throughout, but not 100% on that there, is a chart on X-Fusion website.