I would say I would have on hand or replace with alloy parts the steering arm assembly as from what I have heard (I never broke one) that it can break, and if it does, the big problem is getting to it to replace it due to the amount of dissassembly involved. I had the arms from STRC and that worked great.

I also would have some extra ball studs just in case, and if you focus on having the suspension geometry consistent probably have spare a-arms or go to the much stiffer RPM ones. The stock ones can warp over time.