Not knowing the details of you car, I generally advertise a car for sale rolling, less engine and trans only. That gets the price down where more potential buyers will look at the ad, just by the price listed for the roller. At the end of the ad, then price the engine separately and the trans with converter separately to be sold after car is sold. Leave yourself some room to make a package deal if they want it all together. You don't need to list the NOS at all.