I use a nylon washer on the pots to shorten the amount of the pot shaft that protrudes and enable the metal knob a better fit.
You can use a second pot nut to achieve the same thing and still get conductivity via the control plate.
I periodically buy extra pot nuts from Realtone just for this purpose. In the "olden days" you used to get two nuts with each pot, that cuts into profit too much these days

Plus, a second nut makes the pot bushing height adjustable.