Well, you probably would want to stay with the 5-way switch, and have a 500k pot with a 1 meg tone control. The reason I suggest the VHII/Trilogy/Mule combo is because I've seen some clips with an Edwards LP with VHII's in them, and while your S series is definitely not as thick as an LP/LP copy, the VHII's still sounded wide and fat in that. I also recommended the Trilogy because as you probably know, BKP singlecoils are not hum-cancelling, and something similar in strength to what you wanted(the SD Hot Rails), and since you didn't care if you get real good strat tones, but that can also blend in well with both the bridge and neck.
As for the Mule, it's an obvious choice in placement of a Duncan 59, and judging from some clips, sounds alot better. Really smooth.