I could have sworn that I have seen an E34 with a section in the center partition that had little slots for casettes, am I dreaming or is this a real part...?
I have read-
"cassette box" and "0690 Cassette Box" or "690"
http://www.bimmerinfo.com/option_codes.htm
Even a refrigerator box... "525"
I couldn't find it with the search, just carfax threads.
Hope to hear back!
.Charles