Eliminating white storage rack (9309 rack enclosure)

What would be involved in eliminating our white storage rack in order to
gain space in our data center?  Even though we upgraded from a 620 to an 820
last fall, we still have this huge cabinet (it's three times as big as our
820) taking up space in our data center.  We now have three boxes; the
cabinet, a tower, which was the 620, and the 820.

>From what I can decipher from the rack config, the 9309 has:

2729-001 Multifunction adapter
2741-001 Multifunction adapter

2809-001 Combined function IOP

282C         SI  I/O Adapter

2720-001 Comm port card
2721-001 Comm port card (two)
2724-001 Comm port card
2838-001 Comm port card (two)

Can someone give a little explanation of what these components do???  I
cannot find any info on them on the web. All I have is the description in
the rack config and that does not tell me very much about their functions.
How do I know if all these components are being used?  We are running
Harbinger EDI, FAX/400, PASTHR to and from Japan, and at one time would
access remotely with a Perle controller on two (?) different lines.  The
cabinet also houses a 9348 reel tape system which we no longer use and
actually took off maintenance.

Is this a straightforward project for a business partner?  What would a
business partner need from us besides a rack config to give us a proposal?

Thanks in advance for any help at all.

Bryan Burns
System Operator
ECHO, Inc.
Lake Zurich, Illinois