Installation of key cylinder kit 82-310 that was purchased from Swissco

Interior handle is secured to the exterior handle with thorough bolts from the interior handle through the two holes that have the black grommets as shown in the picture, through the door's frame and into the aligned bolt holes in the exterior handle. The inside of the exterior handle has an upper and lower "stop" feature above and below the provisions for a cylinder to accept fit of the cylinder tumbler "stop" and prevent rotation of the cylinder in the hole.

Question: Per your generic video for "How to Install a Key Lock on a Patio Door", can I "punch out" the 5/8" diameter hole provision in the exterior handle, insert the cylinder as described herein and per the video, adjust the functional length of the tail piece, and remount the handles to achieve functionanlity without the use of a cylinder clip and fastener bolts? Note: Exterior handle does not have threaded holes to accept any clip fastener bolts.

Request clarification of Swisco's response. Understand that I should be able to punch out the hole to achieve keyed access if I follow the method demonstrated in referenced Swisco video. If I punch out the hole, why must I subsequently drill out the hole? I expect that use of a rat tail file to even out the punched hole to accept fit of lock barrel is the second step, not drill out the hole. Additional explanation would be beneficial because the video does not include the drill out step.

Reference last response. 5/8" hole has been created to allow fit of lock set in frame. The inside thumb lever spindle in its normal position protrudes the full depth of the slot such that there is not any available slot depth for the lock spindle to make contact. Must the thumb lever spindle and the lock set spindle be shortened such that they each have contact with half of the slot depth?