Do-It-Yourself PDP-11 help!

[Gordon JC Pearce]

Hi all,
   I've got what I believe is a PDP-11/73 of some sort - it lives in a 
5U 19" rack case with a couple of MFM hard disks, and appears to mostly 
be made of third-party bits.

It *was* working but someone has removed the cards, and now I don't know 
which order they go in the slots.  Perhaps if someone looks over what I 
have they can give me a bit of advice.

I have (plugged into the machine when I got it):

a KDJ-11A - I believe this goes in the top-left space, looking down into 
the sockets
a Baydel B01076 card, with a couple of eproms, a console port, and a 
lead that goes to the front panel (more of which anon)
a Fourth Generation Systems memory board, with 18 41256s on it (512kwords?)
an RXV21
an RLV12
an SCD-DHV11 board
the backplane is labelled "General Robotics Corp", and "P/N 027-0003-OC"

a couple of other boards that weren't in the machine, which are:
a WDC11-C board
an M8044 memory board, 32Kx18 bit

The little front panel has a key switch that switches the mains on and 
off, a reset button with a "DC ok" LED, a Run/Halt switch which is 
broken, and a three-position switch marked "L.T.C. on/off".  With this 
switch up, the LED above it lights up.  "Local Terminal Console" is my 
best guess so far.

When I power the machine up, three of the diagnostic LEDs on the KDJ11-A 
come on, then go off after about 1/2 a second, leaving just D3 on - 
which appears to mean that it can't communicate with the SLU.  Now, I'm 
guessing that means it can't see the serial console, which I believe is 
on the Baydel card.

Do the cards need to go into specific slots on the backplane?  If I 
google for anything in this machine I get lots of sites offering to sell 
me cards, but very little in the way of real information.

Gordon JC Pearce.