How to treat sill plate that is already installed in basement?

I have a finished basement in my house and I realized that the people before that finished the basement did not use pressure treated lumber for the sill plate. I am concerned that the plate will rot with time. I read somewhere that someone drilled holes in the sill plate and injected something called jasco wood preserver into the sill plate that was already installed and drywalled etc... Is this something I can do since I have access to the sides of the sill plate?