I'm replacing the single coils in my old mim strat to 3 dimarzio humbuckers.
I found this wiring diagram in the dimarzio website:
The ground wire from the input jack splits, one is connected to the bridge tone and where should the other end be soldered to?
the split part of that wiring normally goes to the bridge.
On a strat, it goes to the claw that holds the other end of the tremolo springs on the back. you should see a spot to solder, also a small hole through the body.