This is my first replacement of windows, I have done new construction DIY. I don't see a problem in it, due to experience and attention to detail. I have a RO of 32.5 x 36.5. Vinyl window is "American Standard" 32.25 x 35.75.
Question. When I place the window in its place, ensuring that it is plumb, how much room should I leave between the frame and the RO. Please be explicit a simple yes or no does not answer this one.