Yes, it has a compressor! This is the most difficult part of the installation, and was accomplished by handing the tricky bit over to the professional.
The tricky bit is the bracket that holds both the compressor and the adjustment wheel. This was constructed by my local Valiant specialist (Brad at Val Wreck - 97209770). The bracket had to be manufactured because firstly there weren't a lot of slant sixes with A/C compressors (although Brad assures me there were a few VEs fitted with it) and secondly even if there were, they weren't fitted with my extractors, which could get in the way. Pictures will come later.
The bottom pulley used was taken from a hemi: The diameter is perfect but the holes don't match up, so he had to drill two new ones (I think the hemi has four, but the slant only has three). I also had to re-route the fuel line a bit, since the compressor would otherwise have squashed it. This is hopefully only temporary, though, as I intend to put multi point EFI on it when I get around to it.
The next thing on the to-do list is installing the new heater/evaporator. One change I have to make there is that since there is no control for where the air intake is sourced from, I have opted to take the easy road: I'll be blocking up the normal air intake from the plenum and have recycled air only. Making it source the air from the plenum is much harder, and switching from plenum to recycle is more difficult again. That's not to say it's not a possibility for the future: I'm a big fan of a quiet car, and everyone knows that when you switch to recycle you're turning up the noise by about 400%. I tried doing this job last week, but only then discovered how hard it was going to be to include the outside air and replaced the old core. When the old core comes out this time, it will stay out.
One little problem we had was that the fan was too close to the new compressor and would have smashed it to pieces if we'd started the engine with it in place. The fix was a combination of two actions:
1. We put a slightly longer spacer on the water pump. This gives the bonus effect of pulling more air through the radiator and thus making the cooling system more efficient.
2. Cut outs in the fan. We cut out "L" shaped pieces from the fan blades. This matched the original fans, so we didn't feel bad about it.
One other job from last weekend was that I reverse flushed the coolant. Due to several leaks and a broken radiator early this year I never got around to replacing the antifreeze. The result is very brown looking water, and rust isn't the sort of thing you want washing through your nice new system or causing your radiator to block. Cooling is extremely important with an A/C system because:
1. Your compressor is a drag on the motor and causes more heat to be generated.
2. Your condenser (the small radiator at the front of the water radiator) gets cooled first by the incoming air, leaving warmer than normal air for the water cooling.
3. You will be using your A/C mostly on hot days.
Brad said to try it out as-is and keep an eye on the temperature gauge. This is how I tend to do this sort of thing anyway. Obviously if the temperature rises too much I will tweak the system by, for example, adding a fan shroud, which improves the effectiveness of the cooling. It already has a cool thermostat so there's little to no danger of overheating during this testing.
The next option would be a seven bladed fan from a CL or CM. If it's still too hat we'll be looking at an electric thermo fan. Another bonus here would be that it is more efficient, since it doesn't come on at all until needed.
Well, that's all for now. Photos later.
