Is there any way you can paint in a garage ? it would be good to get out of the wind and dust. A 1.4 or 1.6 nozzle would work good. Usually a gallon of paint is needed to paint a full size vehicle. Base clear would be half that because you will end up with double .Use reducer for correct temp and make sure to get all dust off before spraying .Use a gun pre filter and keep compressor drained that should take care of the moisture .