Need some ID's

I'm in the midst of transferring most my 1969 barracuda, into a 1975 duster. In the duster there's a vent system hanging from beneath the dash. I like the way it looks as opposed to the bare 89 Barracuda. Although I think ( I stress ) some of the air doors are vacuum operated. I'd like to keep it for heat/ defrost use only. I don't intend to install air conditioning.
In the engine compartment are a few unfamiliar components. I figure if I can I.D. the stuff I can decide weather it stays or goes. Can anybody explain any of what's in the photo ? Thank you so much.

http://www.forabodiesonly.com/mopar/showthread.php?t=250269
Very cool.
I've pulled the engine already, photo'd, and tagged everything you see. Right now a carbureted Gen III hemi is in the hole. I kept the wiring harness from my 1969 Barracuda wreck that I previously ran that engine in, with all the components still attached.
So now the next thing is. ( whowa ! ) The item furthest to the left is a voltage regulator ? I wish I had posted a photo of both sides of the engine, Cause, there's a voltage regulator by the brake master cylinder also. So I'm confused.
I need to remove the components I don't need from the 75 slant 6, I also need to adapt what I need. I really like the vent system/box that hangs from under the dash, and I want that to operate for heating, and ventilation but properly, I think the heater hose vacuum control valve in the photos opens, and closes, an air door on the interior side of the firewall. Can I just attach that valve to manifold vacuum. The rest of the component ??? Can I just trace the harness back to the firewall, and cut them ? Or is that short circuit hell.
For the hemi all I need is the start, and run wire, a ground. A big #4 wire from the starter relay to the alternator ( that draws the amps away from the ampmeter, I pretty much have that harness in one piece, and it's been fool proof since 2007.
By the way, I've kept most of the air conditioning components if anybody is in need of some illusive parts.
Thanks so far.