If you are just doing it for testing purposes, the Ram charger is not necessary. Just copy the boot files to the Ram drive. Which consist of Prodos, System folder and icons folder, from your SCSI drive.
To make things simple, create a folder called "Ram disk" on your SCSI hard drive. Copy the Prodos file, System folder and icons folder to the newly created "Ram disk" folder. Verify the "Ram disk" folder will fit on the Ram drive. Remove unneeded files from that folder until it fits on the Ram drive.
Now you can just select those three files (Prodos, System folder and icons folder) and drag them to copy to the Ram drive. This does require that you boot from your SCSI when you first start up your computer. But after that, system resets will boot from the Ram drive.
Set up your IIGS control panel to boot from slot #5. Before shutting off the computer, you will have to return the boot slot to the slot the SCSI drive is in.
And lastly, press control-Open apple-reset, to boot from the Ram drive.