Well, most of this is going way over my head but I’ll try and boil it down to psuedo-steps so I can start with this 
What I think you mean is, store an array of pointers to ActorComponents, and their locations in that array too. Store that somewhere, say the GameInstance, and have the missiles read from that? At which point, the missiles first check the locations, then does some Math to work out if they’re valid targets, then if they are it then goes through the pointer to figure out which is the best target based on it’s distance and heat.
My question now is, does that Array manage itself in terms of the locations stored in it? It seems expensive to call GetActorLocation() on those items constantly.
I’ve probably massively misunderstood, I’m still fairly new to programming in general!