Scale drawings in 2 or 3D of mechanical components and piping system rarely formed part of Ship Yard As Built Drawings (SYAB) when the vessel was delivered. Most of the time, only schematic drawings existed just to allow for the shipyard to install Owner Furnished Equipment (OFE) and incorporate in to the Ship Yard provided connecting pipe work. Subsequent maintenance, modification and upgrade is fraught with lack of dimensions and spatial arrangement information to allow for the visualisation of the installation and maintenance space around the components to be replaced. Rig Engineering routinely laser scan the candidate area and conduct reverse engineering and produce a 3D spatial arrangement in the laser scan cloud in a ready state to receive new / proposed components. Using today’s drawing package norms of CAD or 3D component object, the planned system / space can be populated with all the components necessary to make the new system work. A virtual walk around of the planned installation inside the laser scan cloud, can be done quickly to unearth any installation problem well ahead of cutting POs for all the components to make the modifications works first time.