An obstacle detection system for vehicular environments including a monitoring sensor system and a mounting system is disclosed. An installer can make aiming adjustments, in the factory or field, to account for tolerance stack-up. The system includes a housing for mounting the monitoring sensor system to minimize cross-talk and interference between transmitter and receiver sections, to limit sensor system movement, and to enable gross and fine aiming adjustments. In one embodiment, a circuit board is disposed within a cradle assembly which, in turn, is mounted in or integral to the housing to position the obstacle detection sensor as necessary. The cradle in one embodiment is an enclosure for the circuit board. The sensor housing is mounted to the interior vehicle trim, door panel, and/or door sheet metal and ensures consistent mounting regardless of interior trim or factory installation variations. Integral adjustment mechanisms are incorporated for adjusting the orientation of the sensor system. The circuit board may be comprised of plural subsections interconnected by flexible circuit board, enabling accurate alignment of each subsection with respect to the environment to be monitored.