Almost there - a supplier for the drives says he does not have the rails - are there supposed to be any? I can't see anything on the 6607, at least, that looks like rails. But these are the 6713s. So maybe you know.
No rails needed. Just screws for drives 1,2&3 (cage). The 4th drive
uses the bracket you previously described.
6607 and 6713 drives are physically similar (jumpers, mountings). The
exception is the 2/3 height drive (6713 DCHS 8gb) which is harder to
install because of it's size. The more common DGHS 8gb look the same as
the 4gb drive (1/2 height).
You must jumper the SCSI addresses manually. The chart on the inside of
the left panel tells you what they should look like for each device.