The SCCA’s Spec Miata rules require that the steering lock be disabled. On SpecMiata.com, there is conflicting advice on how to go about this. Some posts suggest drilling through the face of the mechanism as shown below:

There's a better way

Actually, drilling like above potentially causes issues with the steering sometimes locking when the ignition is turned off and prevents key removal. The better way to do this is to drill from below (as suggested by Dave Wheeler in his Spec Miata Maintenance and Construction Manual).

If you drill just into the center of the plate below the location shown above (I used a 3/8″ drill bit), then you will see a spring sitting there. Removing this spring disables the steering lock without any adverse sides effects.