Here is what was required with Lion. I cannot guarantee it will help with Mountain Lion since you may have the error stating it could not install because it failed to find a Recovery HD partition.
What to do if the installer warns that no Recovery HD can be created
Some disk partition configurations may result in the OS X Lion installer reporting that it could not create a Recovery HD. In these situations, even if you are permitted to continue the install, you should quit the install and create an external, bootable OS X Lion hard drive with a Recovery HD, first. You will be able to return to the upgrade to OS X Lion on your computer's boot drive after creating the external Recovery HD.
- Your storage device must have at least 13 GB available (after formatting) to install Lion and an Internet Restore partition.
- These steps will erase and reformat the storage device. OS X Lion: About Lion Recovery will instruct you on setting up the storage device to use the GUID partition scheme and the Mac OS Extended (Journaled) format, which are required to install Lion and an Internet Restore partition on your external storage device. You should back up any important files that are on the device to a different drive.
- This procedure will install a version of the OS X Lion that is compatible with the Mac it was created with. Using this Lion system with a different kind of Mac may produce unpredictable results.
- Your computer's serial number will be sent to Apple to help authenticate your request to download and install OS X Lion.