I basically got sent a scene that built from a bunch of copies. I'd like to convert to instances. I did some search, but googling "convert object to instance" or anything like that results into "convert instance into object". So that wasnt really succesfull. Tried searching for some scripts.. couldnt find one either. So if…
I don't think there's a maya command to directly covert an object into an instance of another. Instances can only be made from duplicating (AFAIK) (edit: or via 'instance' procedure). A script could be made for this tedious job, though. How many copies do you need replacing? PS: are the transform handles of the copies…