That would be me.
But this was a shortie with a fiberglass body-and sliders for windows.
It was easy peasey. I started out looking at it debating how tough the job was gonna be and just planned an exploitory putzing -unscrewed the 20+ screws-told the wife "put your hand on the window here + hold it in while I poke around-pushed it out + turned it over. Poof-right in place. "Hold it 10 more seconds while i go get the silicone." Laid a bead + set it in place. Hold the trim piece up inside (mAKE SURE YOU PUT IT THE SAME WAY IT WAS ON THE WINDOW BEFORE-OR THE RANDOMLY DRILLED HOLES WONT LINE UP!)
I bet it didn't take 20 minutes.
Afterwards, you need to do a little drain re-routing. Silicone up the original holes, drill a couple holes in the rubber on the bottom.