I bought a house with newish but bottom of the basement white vinyl windows. I'm looking to replace them with either a steel window or an aluminum window from a company that makes TDL aluminum windows that closely resemble old steel windows.

Here is the problem: My current windows are flush with the exterior stucco. No matter how nice the windows I get are, they aren't going to achieve the classic 20s or 30s cottage look if they are flush with the exterior. Currently, there is an interior window sill so I'm wondering, with new construction windows, will the windows be able to be mounted further inboard so that they are inset from the exterior? I want the stucco to roll around the corners of the window openings about 1.5-2" deep.

Will I need to make the walls thicker by replacing the 2x4s with 2x6s?

Thanks for your help.