It can be done. But good pint the humbucker is a better candidate.
I have Maxon pickups from the late 70s with single wire for hot and outer braid is ground
I still managed to coil split them by carefully soldering a fly lead to the serial link wires between the coils and I put the bridge on a push pull for out of phase by putting the cable in a heat shrink tube and exposing the last 3 mm of braid which I tinned. I hooked the hot pickup wire to one middle terminal on the push pull and the tinned the opposite middle terminal. I then brought the tinned braid to the tinned terminal and heated the braid so the solder flowed between terminal and braid. Just like how I would ground the braid to the back of a pot.
It's fiddly but can be done.
Heres my coil split wire :
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