For sure use the rubi shocks. The jury is still out on any difference in the springs but I’d swap those since it’s easy. Does the RC kit come with control arms? If not I’m 99% sure the rubi and sahara control arms are identical so I world not swap those (PITA for no gain).
I put a 4 ½ inch full lift kit on with a friend and neither of us had done anything like that before. Follow the instructions and take your time, it’s not hard. Think about safety and put a couple of you wheels under the Jeep just in case it slips off the jack stands.
BTW, I wish I lived near you, a kegger sounds like a good deal