According to a post in thread I found searching Google groups for win98 pscript.drv download, you should be able to get SE to install pscript.drv by installing any Postscript printer:

"Simply copying a DRV file somewhere won't work and won't make it any happier than it already isn't. Click Start, point to Settings, click Printers, doubleclick the add a new printer wizard and have it install a PS printer."

If that doesn't work, the file can be downloaded from  Printer-Drivers.com (free registration required).

Jim