I may just put air, which is 80 nitro anyway. I can put in welding gas, but I need to get a fitting - no big thing. However, with the reservoir:
1) The larger air chamber won't allow air to heat up as much as if it was in the small shock reservoir, (the shock should be filled with nitro anyway, but I don't have that here)
2) I can up the pressure, or lower it on both shocks at once instantaneously. I can also keep a check on the shock pressure, which I couldn't do before. This is important for those who load their vehicle down with gear for hunting, or like I did, with an extra seat and two people in the back.