This era of switch has bare spades and a protective rubber boot covers the connections:

Later switches have a sub-harness on the switch with a large multi-plug for connection to the main harness and no cover. 1975 V8 (Vee) full energy-absorbing column with side entry lock (reputedly the final type as used on V8 and all RB cars) - on the bottom of the lock with the left-hand cowl removed:

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In this case a recessed grub-screw, still recessed when the switch is freed, be careful it doesn't fall out of its own accord when your attention is focussed on the switch as it is very small. It screws into the lock body and has a projection that fits into a recess in the switch body, so I kept the screwdriver in position while I pulled the switch out, then screwed it back in so as not to get lost:

Note the switch is fully recessed into the lock, some switch bodies protrude from the lock body. Unless pushed all the way in it may not fully engage with the lock and fail to operate correctly. The hole closer to the switch entry is possibly an alternative screw position for other switches.

The screw locates into a hole in a tab on the switch:

Late UK RB, with a countersunk head screw through the lock body closer to the lock. Both this and the 75 V8 lock above were made by Neiman: (Crispin Allen)

Early LHD side-entry lock - round-head screw facing the driver, although the edges of the socket seem to be peened over into recesses in the switch as well:

Later LHD side-entry lock, round-head screw under the lock, closer to the edge of the switch entry than Vee's lock as pictured above:

As there were a number of different lock manufacturers, it's possible the switches varied as well, which could mean marrying an original switch or lock to a replacement could be tricky. In Bee's case (top image) the original switch fitted the new lock without problem, but as can be seen above there were two different RB arrangements from the same manufacturer.

Late UK RB switch opened up for cleaning and lubricating (with Vaseline), which was all that was needed to fix a lock where the key could not be withdrawn: (Crispin Allen)