I'm not sure whether or not he'll be glad he's got the wipers and vent system after the car's done. All I know is that I'll be glad he's got them. That blower is gonna restrict his vision already. I don't want a fogged up windshield with dew or raindrops making matters worse.
We tend to sell off unused parts at a significant loss just to get them out of our way. I don't know how much of a demand there is for the vacuum setup. - Maybe from guys that buy a Charger without a front clip?