Hi Dave,

I would do a test run of the mixture before using it on a model. Back when Floquil was the "go to" paint I was looking for a way to get a faded  appearance on some single sheathed boxcars in grain hauling service and was warned not to add white  as it would turn the red to pink but to use a  buff color.. I can't say if the white would have turned the red pink as I never tried it.

Good luck, Walt