Abstract: A method designed to replace a compromised instrument case with a new case without the need to disconnect any wire, relay or any other electric equipment is described herein. The instrument panel is supported for example by a temporary support frame during the dismantling of the old case and the assembly of the new case. The new case is therefore assembled on site around the instrument panel. The new instrument case includes a floor which is made of at least two parts, one on each side of the wiring. The instrument case therefore remains in a normal working mode during the entire replacement procedure thus preventing downtime. As well, the amount of manpower required for the replacement of an instrument case is drastically reduced.