Replacing Central Administration on a corrupt server

I was handed an issue whereby one of the SharePoint servers in a farm had fallen apart. For reasons I won’t go into now, this application server had been rolled back so that all that remained was a clean windows 2008 build. There was not a hint of SharePoint on this poor thing. The task was to reintroduce this server to the farm.

This sounded straight forward at first but was made a little more complicated by the fact that central administration was on the machine which was lost so I was unable to make any farm alterations this way.
The farm in had two web front ends and cluster sql boxes. The dead application server waited to join the farm.

My approach was as follows:

1. Back up existing farm settings and content - Log on one of the web server and Back up IIS websites, 12 hive and main site collections.
2. Run SharePoint products and technologies configuration wizard – Run wizard on web server and configure to install central administration on this web server.
3. Remove redundant server from farm – Navigate to central administration and remove the application server from the farm (via operations -> Servers in farm -> Remove server). This updates farm so that there is an accurate representation of server architecture. 
4. Install SharePoint on Application server and connect to farm - Log on to application server and Install SharePoint and connect to existing farm.
5. Run SharePoint products and technologies configuration wizard – Run wizard on Application server and configure to install central administration on this application server.

Hey presto, you have a central administration up and running again on the correct server.