Drill four 1.5mm~2mm(1/16"~5/64") diameter, 3mm(1/8") deep holes at the left and right side of panel at the position corresponding to original LCD panel. Do NOT drill the glass!!.
2 will be drilled on metal and then plastic, 2 on plastic. As said before, the metal is very hard! use high quality drill and be patient and avoid overheating, or you'll burn your hand or the plastic and LCD glass.
In these pics, the upper LCD is the original one, the bottom one is HV121P01.