I did the same wiring on my 7 String Dean Vendetta with a Liquifire and a Crunchlab, sounds great, but I had to give it to an experienced tech and even he was nearly driven mad. Itīs supposed to be the wiring Petrucci uses and it can be found on music man guitars, but try getting any information about that. Dimarzio germany didnīt know how to do it, music man germany had no idea,...turns out music man uses a curcuit board, no wiring. Finally we ordered a very specific switch from dimarzio (donīt know exactly which it was anymore, would have to look for the packeging, though the number on itīs side says 48096). Itīs not a big switch at all, should fit any guitar I guess.
Long strory short: Yes, it is possible. Yes, itīs complicated. Worth it? Hell yeah.
With my PUs it gives me the best of two worlds which is a great stratesque rock sound with that certain dirt and old schoolness in it. I love it.