Here are the pinouts for the motherboard connectors, including the RDnn disks.
VAXstation 2000 System Jumper
(on KA410 motherboard about an inch or so directly behind the thin ethernet
  BNC connector)
VAXstation 2000 - jumper on pins closer to thin ethernet BNC
MicroVAX 2000   - jumper on pins farther away from the thin etherner BNC

VAXstation 2000 Connector Pinouts

Printer port (J3)
1 - ground	2 - xmit_data	3 - rcv_data
4 - no conn	5 - +12VDC	6 - no conn
7 - ground	8 - ground	9 - fer_ena (jumper to pin 8 for console)

Video Connector (J5)
1 - vid_red	2 - color_ret	3 - mono_ret
4 - +5VDC	5 - mouse_rcv	6 - kbd_grnd
7 - ground	8 - +12VDC	9 - vid_mono
10 - vid_green	11 - vid_blue	12 - -12VDC
13 - mouse_xmit	14 - kbd_rcv	15 - kbd_xmit

Comm Connector (J10) - RS232 with partial modem control
Tape Port Connector (J13) - single ended SCSI

RD/RX Cable Pinout (J7)
1,3,5,7,9,11,13,15,17,19,21,23,25,27,31,34,37,40,43,46,48,51,54,57,60 - ground
2 - lospeed
4 - rxindex
6 - rxsel0
10 - moron
12 - rxdir
14 - rxstep
16 - rxwd
18 - rxwrgt
20 - rxtk00
22 - wrtprot
24 - rxrdata
26 - rxhsel0
28 - rxrdy
29 - rdhsel3
30 - rdhsel2
32 - rdwrgt
33 - skcompl
35 - rdtk00
36 - wrtfault
38 - rdhsel0
39 - rdhsel1
41 - rdindex
42 - rdrdy
44 - rdstep
45 - rdsel0
47 - rdsel1
49 - rddir
50 - dselack
55 - rd0_wdath
56 - rd0_wdatl
58 - rd0_rdath
59 - rd0_rdatl
8,52,53 - no conn

Expansion Disk Data Cable (J9)
2,4,6,8,11,12,15,16,19 - ground
3,5,9,10,20 - no conn
1 - dselack
7 - +5Vdc
13 - rd1_wdath
14 - rd1_wdatl
17 - rd1_rdath
18 - rd1_rdatl