Hi, I am going to replace a couple windows on my house. the interior has been stripped to the studs. Here is my problem. The siding on my house sits directly on top of the studs. Since I don't want to redo the entire wall, I don't think it would work for me to apply plywood to the studs before retacking the siding.

How should I hang the window? All the only DIY instructions assume some interior sheathing or plywood beneath the siding. I wonder if there is anything I should do to weather seal the siding before I put it back up against the bare studs. As it stands now, my plan is to frame out the window from the inside. Remove the siding from the outside, insert the window, attach the window directly to the header and studs, replace the siding on top of the window flanges.

Any thoughts?