WPI: How to install software in a different partition (other than C:)

WPI: How to install software in a different partition (other than C:)

I want to use the Web Platform Installer 4.6 to install things like MySQL
and the Microsoft SQL Server. However, during the installation process, I
don't see an option to select a different disk drive for the installation.
In my case, I'd like to install MySQL in the E: drive (not in C:). The Web
Platform Installer installs all software in the C: drive by default.
How do I install software in a different partition (other than C:) with
the Web Platform Installer?
JP