At our fabrication facility we use a theodolite laser system. We had hard orientation targets on our assembly jigs to align the actual model to the laser.
The system works by tracking a "target ball" that has a set of mirrors in it to reflect the laser back to the unit. The target ball also has fixtures that can be used to track surfaces, edges and holes.
It has a frequency pulse sweep through the laser that it uses to measure distance.
You can track in real time if you have a theoretical model. We've actually located complicated parts using this system.
There is a range to it due to the light dispersal. We've always oriented the laser unit fairly close to the aircraft. We were able to acheive a tolerance as tight as 5 ten thousandths.
However, you will need a direct line of site for this system. The theodolite machine cannot be moved during a shoot. The machine is very sensitive.
Someone walking close to the machine or dropping a tool near the machine will throw it off due to the floor vibration (even through concrete floors).