You mixing two things in one sentence which a little confused me.

Contents of HDD is not the same as HDD image. Contents are files and folders from filesystem(s), while SBS (sector by sector) image is whole structure, dumped as is (instead to sparse one, which is not possible to make in this case).
If You will create HDD image (must be encrypted for this task, so option no. 1, everything else results in recognizing HDD as empty) and restore it on larger HDD, You will
not get extra space because custom partition table covering up old size and we don't have tools to edit both: partition table and UFS2 filesystem table to fit into new size. So it is kind a crippled cloning type and main purpose of "
PS3 HDD Dumper" is not cloning but sharing image or just having full copy (i.e when user don't have/cannot dump EID Root Key, needed for decryption). Another issue is HDD assigning, so if You want restore disk image on different HDD, You must first making format of this HDD on target PS3 because doing that, she also assigning this HDD (noting model number, fw version and serial number of this HDD). Sony did everything they could to not allow user changing disks just like that without cleaning them first.
For You is "
PS3 HDD Backuper" script which will copy important data from PS3 HDD and which You need to restore it by hand at this moment (from USB using file manager on PS3 side or FTP client - because I didn't write yet restoring script).
Take in mind that this script wasn't very well tested and just in case, user should check after copying if everything has been copied. Also take in mind that if You have dead CMOS battery in PS3, You shouldn't backup in the same dir after making changes because files aren't copy just like that, but syncing using rsync (it checks time stamps in files and copy only differences between target and source dir).
If You want do all of this manually, here is guide describing where is what exactly:
https://www.psx-place.com/threads/ultimate-userdata-backup-guide.29037/