The Dragonfly Spectral Line Mapper: Completion of the 120-lens array

The Dragonfly Spectra Line Mapper (DSLM) is a mosaic telescope optimized for ultra low surface brightness imaging of visible wavelength line emission. The design is based on the Dragonfly Telephoto Array, with the addition of ultra narrow bandpass filters in front of each lens. The telescope was constructed in four phases from March 2022 to November 2023. Since the original 10-lens phase, various hardware upgrades were introduced. Here we describe the construction and commissioning of the complete 120-lens array, as well as the implementation of various hardware upgrades. Additionally we present updated characterization of the cameras and filter transmission for the full array. Finally, we reflect on the construction process and remark on the feasibility of a larger 1000-lens array.