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The NASA DART impact into one component of the Didymos-Dimorphos binary asteroid occurred on UT 2022 September 26. Images taken at the impact time show a spectacular comma structured cloud of ejecta and comma on later dates comma the emergence of a long comma radiation-pressure swept tail of particles. Here comma we propose a 4 orbit program to observe the DART-produced debris some 10 weeks after the impact comma from a perspective within the projected orbit plane of the system. This observing geometry comma in conjunction with an existing dynamics model comma will provide a unique measure of the quantity and of the size and velocity distributions of the larger ejecta particles comma and we also expect to detect individual macroscopic fragments (boulders) in the ejecta trail. The measurement is highly complementary to the 19 orbit HST program GO 16674 comma whose final observation was taken on October 15. The proposed observation will extend the time base of data from less than three weeks to ten comma and provide the strongest ejection constraints and the ultimate record of this unique impact experiment. Having an exactly known impact time and projectile energy comma the DART impact also provides an important means to interpret existing and future observations of colliding asteroids comma which are also known to produce structured ejecta fields and long trails of debris.