From my understanding (not experience) the pits tend to not like anything thats not factory and brand spanking new lol... Even if it does make the car safer
I may have misunderstood your question, but if you have no reason for the intrusion bars to be in before your car goes to the pits, i would suggest waiting till afterwards...
As for jdm doors, dont think there is much difference... correct me if im wrong though, shouldnt intrusion bars be fixed between the base of the A and B pillars (preferabley to a cage) rather than the door?