Everything you need is here, except the parts are ID'd by part number, not size:
http://www.faxonautoliterature.com/Search.aspx?k=engine+equipment+assembly&c=30737These are factory "engine dress" drawings used at the car assembly plants (not the engine plants) to add the options such as PS, A/C, auto/manual trans. Same publication also exists for '69 Dart at Faxon.
I have a '69 340 with factory air, no PS. This is what I know:
Crankshaft pulley to A/C water pump pulley ratio is 1.3:1 size-wise, which yields 1:1.3 rpm-wise, so the fan is turning 1.3 times faster than the crank.
A/C uses 5-3/4" water pump pulley (hard to find) and a 3-1/2" diameter 6-vane water pump impeller to make the fan run faster and cool more. Non-A/C uses 6-1/2" pulley with an 8-vane, 4-3/8" diameter impeller. Both pulleys pump the same amount of coolant per crank revolution, but the 7-bladed fan is running faster on the A/C's smaller pulley. Many parts dealers selling water pumps don't know about the 6 or 8 vane impellers. I suspect many 340s out there have the wrong number of vanes and the owners don't know and it doesn't seem to make that much difference. But the 5-3/4" pulley is surely important for Nevada.
Given that the crankshaft pulley to water pump pulley ratio 1.3:1 and the water pump pulley is 5-3/4" then the crankshaft pulley is 7.48" (or maybe 7-1/2") diameter at the water pump belt. But never mind, because according to the manual above there is only one 3-groove crank pulley for 318/340 with either A/C or PS or both, and there is only one one-groove crank pulley for 318/340 with neither PS nor A/C. At least this is the case for 1969.
In the photos above, the fan spacer is non-factory for A/C in '69. Factory was a thermostatic fan clutch. That fan or water pump pulley looks to be the correct 5-3/4" for A/C. There is only one harmonic balancer for '69 340 regardless of PS, A/C or not according to the drawings above.
First the 68, then the 69 340.
