Don't get too despondant.
First, your Squirrel interface is the Classic Squirrel, as manufactured by HiSoft, just rebadged by Power Computing.
The drivers will work on any Classic Squirrel device, original branded or not.
Did you install the Classic Squirrel update? The last dms file is on the FTP site, named sqs_dsk.dms. The other .dms file is for use with the Surf Squirrel only (it will have a 9pin serial port on the back of the Squirrel)
What version of Workbench are you using?
What version of SquirrelSCSI do you have in your C: directory.
What version of squirrelscsi.device is in your DEVS: directory?
Have you modified your CD0: mountfile in DEVS:DosDrivers/ (or SYS:Storage/DosDrivers/ )?
If you are using WB3.1...use DMS to write the sqs_dsk.dms file to a blank floppy disk, and install from the newly created floppy.
If you are using WB3.5/3.9...use the installer on the new floppy, but you have to modify your S:Startup-sequence, and place the line C:SquirrelSCSI BEFORE C:Setpatch QUIET line. Check your S:user-startup file afterwards, because as i remember, the installer places the C:SquirrelSCSI command there...remove this, because you don't want the resident driver starting twice. During the installation, make sure that the dosdriver gets put into storage/dosdrivers first...if you don't get that option during installation, copy it from DEVS:dosdrivers to storage/dosdrivers after installation, making sure that no CD0 mountfile is in DEVS:dosdrivers.
Reboot your system...and fingers crossed...you should be up and running. I installed the same drivers earlier this week, so i know that they work okay...didn't need the 68060 patched files though...
Let me know how you get on...
Rob.