I don't get it? You choose the drive to install windows and that's it! Nothing else will be install on other drive. I install windows 8 about 3 to 4 times a week on computer with multiple hardrives without any problem. Lievre
There is one situation where files will be installed on another drive. First you have Windows installed on a HD. That disk is set in the bios as the boot drive. Then you install Windows on a different HD without changing the bios. In this situation, install will want to write some files to the first HD.