Blend control knob instead of a 3 way switch for a pair of single coils?

As long as your keeping the tone knob functional I say do it.

Don't conduct a blend control experiment using a drill or any other permanent modification. Use a stacked pot assembly first and see if you can get the blend effect you seek. My bet is you will not, hence the reason I say use stacks at first before you start drilling. Use the bigger bottom rings for pickup volume controls, the small cap knobs for tone controls.

For singles, my choice would be CTS 250K/250K concentric pots. Get knobs sized for imperial, not metric, pot stems.



Edited to correct pot K values