You could, but be sure to do the following:
1. Check if both disks are fiber. I know 880, but not sure about 280.
2. If you could swap disks, you'll have to boot from cdrom and copy all the "/dev/dsk", "/dev/rdsk", "/devices", "/etc/path_to_inst", and "/etc/devlinks.tab" from the cdrom into the new disk.
3. to copy use tar:
tar -cvf - *|(cd <newdir>;tar -xvf -)