To the question: Do I condense the ground and power from the lights down from 4 wires to 2?
Yes, if you are using heavy enough wire to handle the current. I think the other question not asked, but related is "can I do both lights on one relay?"...same answer.
EDIT: OK I looked at the linked thread...the fuse block part confused me. If all you are wiring is the lights: Blue=power from your switch, wire your lights in place of the terminal block. If you want other, switched accessories (on/off with the ignition) then your lights become one of the accessory blocks listed (i.e.. vest, gps, etc) and you will want another relay on that circuit wire 87 (red) to + terminal, 85 (blue) to switch, 86 (Black) to - terminal, 30 (red) to lights, return (black) - from lights to terminal.
06 DL-650 Wee-Twin Baby!!
86 XL-600R Old School Adventure!