Yes. Most all desk accessories (DAs) written for System 6 run under System
7. To use a System 6 desk accessory, you must first take it out of its
"suitcase". Follow these steps:
1) Locate the desk accessory. It should appear in a file that has a
suitcase icon. (Unless it was already part of the System 6 System file -
in which case it would be in the System 7 System file.)
2) Open the suitcase icon by selecting it and choosing Open from the File
menu, or by double-clicking on the suitcase. The suitcase will open
into a window and show the desk accessory inside.
3) Drag the desk accessory out of the window and onto your hard drive.
You can put the desk accessory anywhere on your hard drive. If you want
to access the desk accessory from the Apple Menu, put the desk
accessory in the Apple Menu Items folder.
Some desk accessories, like spell checkers and art effects, will need
special installation procedures to work properly with System 7 (they may
need to be installed in the System file, though Apple does not endorse or
recommend this method). Check with the software developer for additional
details on using these DAs with System 7.