No, I can not get 25-32 MPG, but your Focus will look real sad with 6000 pounds of rock in the trunk. My heavy duty can do that at 12+ MPG.

As far as water injection it is used more to lower the temp of your charge air from what I have read. It needs to be injected at rather high PSI through a nozzle that mists it rather fine. Then the evaporation cools the air around the water droplet.
I also read the methyl alcohol does create some extra boost out of the turbo when mixed with the water injection at 50/50 mix.
I will try to find the info I read.