High fidelity brain recordings have enabled the development of sophisticated closed-loop brain-machine interfaces (BMIs) in which electrochemical signals generated by the brain can be used to control machines. This technology has great potential as a therapeutic tool for spinal cord injury, epilepsy, stroke, and other neurological disorders. A key challenge towards implementing BMI technology in medicine is the development of a fully implantable and chronic neural interfaces. This work details the assembly process for a 0.8mm x 3mm x 1mm implantable sensor mote for neural dust, a wireless ultrasonic backscatter system which may provide a path towards truly chronic BMI. Design constraints are delimited and failure modes from previous attempts are explained. Additionally, this work suggests possible improvements, extensions, and variants of the neural dust system for other neural and non-neural applications.