A bonnet lock is available as a special accessory in kit form comprising two lock assemblies.
Cover the area, forward of the bonnet catch lever, with white masking tape. Use a pencil to mark the position of hole as shown and dimensioned. Open out the hole to 5/8" (15.9mm) diameter, and shape the hole as dimensioned. Remove the tape and paint the edge of the metal to prevent rust formation.
Assemble the bonnet lock details in the sequence shown.