Welcome to the forum!
We don't have an issue with threadmancy here.
Old threads have valuable information for new people, as evidenced by your question.
Never understood why people get their undies in a bunch about posting new things on old threads.
I know it looks like the rear red line is shorter than the middle one.
That is due partly to me goofing the line, and partly due to weird camera angle stuff.
But trust me, the rack gets wider toward the rear, and the measurements are 36.5", 39.5", and 41.5" as you go back.
The depth varies because it is bowed, and has that instrument cover in the middle.
Most of the rack is 13" deep, but it narrows to 9.5" in the center.
Keep in mind also that the front rack is also the hinged lid of the front storage compartment, so you might not want to mount anything on it semi-permanently - at least nothing heavy.
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