Here is a few pics of the re-worked rack.
Re-installed, with all my rack-mount stuff installed (one amp needs to be moved down a slot, may eventually paint the NEC switcher black)

A closer cross section shows - some rough plaster, the painted wood lining the opening, the rails, and part of a vented blank

Back o'the rack-

Now here is what I am thinking about the door. The doors are made for full racks, and the instructions suggest on a full rack you just install the hinges on pre-machined slots, and walla. With rails only I will have to improvise. Calvin gave me a few pics
in his thread which showed me how it sits in its natural setting.
My plan is add trim over the wood and plaster, flush with the inside seam of the wood, and the door will rest on the trim (to be painted black).

I would then just add the hinge to the meaty part of the trim, piercing it, and ultimately anchoring in the wood behind it. My fear here is that the trim will split (it comes in pine)

For context, the top hinge just rests on top male/female style

Then next concern is that the keylock will need to "lock" by cutting a slot in the trim. From what I have seen on the web/tv, a biscuit joiner would be ideal for this - I don't have one of those, so I will have to try a manual cheaper tool. I am thinking either perforating with a drill and then a knife, or maybe the hand-held drywall saw I just picked up.

Any flaws?