We present techniques for automatically identifying relationships between rigidly linked 6DoF and 3DoF sensors belonging to different sensor systems. The techniques allow for subsequent automatic alignment of the sensor systems, increasing the usability of modular sensor systems. Two techniques are presented and analysed in simulation and a case study for performance under varying noise and latency conditions. Good results were achieved, with each sensor identified correctly in at least 60% of estimates, or 4 times greater than random selection. After a sample collection period of around 5 seconds, the matching is performed in less than 5ms and is scalable to noisier systems by using more samples. Our methods represent a key step in creating highly accessible modular multi-device 3D systems.