If I May Contribute:
Just wired up my BP9 lights. The sidemarkers are straightforward enough to anyone who would be attempting this. The wiring for the lo/hi beams is a little more complicated.
I used an aftermarket 3 prong male/female harness to make everything tidier. (neglected to take pics, but can provide if someone really needed it)
Wiring for BP9 harness to stock BP5 harness is as follows:
Drivers Side:
BP9 Red to BP5 BlackRed for Power
BP9 Black to BP5 YellowWhite for Low Beam Toggle
(third prong reserved for Hi-Beam toggle, power shared in splice to BP5 BlackRed)
Passenger Side
BP9 Red to BP5 RedGreen for power
BP9 Black to BP5 YellowBlue for Low Beam Toggle
(same mating of hi-beam splice as done on drivers side)
I went straight off the ballast with the HID wiring, but that was just my way of keeping things clean on the back end)
My instructions may only make sense if you're in the middle of actually wiring these things up, so dont be afraid to dig in and then consult these notes LOL