If the correct position for the hole is on the centreblock do you need to bother with all the hassle of gluing a piece on the side of the centreblock? Seems to me that simply plugging the hole and redrilling is going to be plenty good enough, and with getting a piece glued on the side of the centre block being high risk for glue spills and blood pressure, not to mention exceedingly hard to do, I wonder if it's worth it.