Right now I am pretty tied up with work this coming week-but hopefully this weekend I'll have time to scrub the bottom of the rack back out and get the HV transformer bolted down, and the control/interlock transformer wired in and start wiring the interlock circuits for things like the rack door.
I think it'll be worthwhile to have interlock switches mounted for each of the transmitter's chassis decks-the intent is to build an RF deck on rails, so the rack cabinet screws can be removed, the cabinet slid out, and tubes changed/settings tweaked without having to get behind the rack. Interlocks would be vital for that kind of feature on any HV wiring, so I think any section that is on sliding rails will have to have one.
The only issue with having the modulator deck slide out of the rack is the weight of the modulation transformer-the Kenyon T495 is not a lightweight! (even though it is undersized for the job)
If you want to pull the sections out of the front and have them on plugs in the back of the rack they will interlock themselves but then you'd need test cables to be able to run anything with the sections open. If you have them on cables without plugs you'd have to bypass any interlocks to do any adjustment under power.
My Gates has to be accessed from the back and there is 50 years of duct tape residue around the single interlock switch on the back door. I'm going to install a couple of red lights in the back to tell me that the LV and/or HV is on in the transmitter just to be safe but I'll still check and use the Jesus stick.