I followed ImA4Wheelr’s approach ("Police Light" Version 2 - 14500, Nanjg 105C, & XP-G2 Q2 7C4), and used a copper coupler from Home Depot that I cut down as the “pill”, and then soldered the driver to one end and attached the quad emitter board to the other end.
The driver was the smaller one from Lightmalls that is in this thread (Anyone worked with either of these drivers from Lightmalls?) with a slight resistor mod (parallel to the R200), and heavy wires for the emitter (24 AWG?).
The quad board was from illumn.com.
The Carclo optic was from ledsupply.com.