You want at least a couple 5-8 millimeters of adhesive on either side of the holes, I would recommend as wide of tape as will fit on the surface with the holes drilled, the tape can even cover the rounds on either side a bit. So in the x-section you posted, 25mm wide tape or rim strips could easily be used. I tend to think the tape is easy and cheap but some people prefer the Bontrager Rhythm 22mm wide rim strips. You just do not want the tape or rim strip to interfere with the tire sidewall.
