Another page on this site offers AppleScript-based wrappers for BasiliskII running System 7.6.1 and SheepShaver running MacOS 9.0.4, complete with file-transfer and printing features built in. This page offers something simpler: customized versions of BasiliskII and SheepShaver that contain (respectively) standard installations of System 7.6.1 and MacOS 9.0.4 without the AppleScript-based printing and other features available from the downloads on the other page.
Both these apps work the same way. Download them; move them to a different folder from your Downloads folder (to avoid an error message from macOS), and launch them. Each will open a standard, mostly unmodified version of the Mac operating system. The System Seven app contains a folder of installers that I have found useful. The MacOS Nine app has had some Control Panels and Extensions disabled in an attempt to make it load more quickly.
You may download these applications here (both are notarized by Apple):
When launched for the first time, each app creates a folder in your Library/Application Support folder named System7 or MacOSNine. It then copies a ROM file, disk image, and prefs file into those folders. (For MacOS Nine, these files are copied into a folder named MacOS.sheepvm inside the folder; Ctrl-click on that folder to view its contents.) This makes it possible to keep the apps in your Mac's Applications folder so that each user on your Mac can have a separate disk image and preferences.
You can customize the default prefs file for each app in the Application Support folder, and your changes will be remembered. You can restore default settings by deleting the prefs file or the disk image or both; they will be recopied the next time you launch the application.
When the app is first launched, it checks the system locale; if the locale is US or CA, the prefs file contains the line keycodes false but if the locale is anywhere else, that line reads true instead of false. You can modify this and other settings in the prefs file at any time.
The boot disk images are named basiliskii.sparsebundle and sheepshaver.sparsebundle. You can add disk images by making one or more copies of the default sparsebundle, in the same folder, named second.sparsebundle, third.sparsebundle, or fourth.sparsebundle, and they will be mounted automatically when you launch the apps. You can then initialize the copied disks to create blank disk images. You can also drag or copy other disk images into the same folder, and rename them second.dsk, third.dsk, and fourth.dsk, and these too will be mounted automatically. (The images can be in .img, .dsk, .toast, or other formats; rename them second.dsk, third.dsk., etc.)
If you want to boot to an installer disk image, copy the installer disk image into the same folder with the other disk images, rename it installer.dsk, and lock it in the Finder. When you boot the app, the installer disk should mount as the boot disk. After using it for installation, unlock it in the Finder and rename or remove it.
You may want to run System 7.0.1, 7.5.3, or MacOS 9.0.1 instead of the default systems. To do this, make a copy of the original app, replace the sparsebundle inside it with a sparsebundle with the OS version that you want to use, and change the name of the app to something like System 753 or MacOS 901 (no periods). This will break notarization, so before you run the app you will need to open a terminal, type in the string xattr -rc followed by a space (the space is essential) and then drag the modified app into the terminal, then press Return. When you launch the app, it will create a folder in your Application Support folder named something like System753 or MacOSNine901, and copy the needed files into it. This lets you run multiple versions of the OS without problems.
Please do not ask me to help you customize the "classic" Mac OS or advise you about any applications. Please ask for support in the E-Maculation support forum for BasiliskII and SheepShaver
If you find this system useful, please feel free to make a contribution via PayPal from the link on this page.
Edward Mendelson (em thirty-six [at] columbia [dot] edu, but with two initials and two numerals before the [at] sign, not spelled out as shown here).