Hi Rob,
You've got good instincts here; the second capacitor will indeed substitute for the original one just fine.
And yes, when you're wiring it up, ignore the positions of the wires coming out of the device and wire it strictly according to the colors of the wires. The two grey wires are actually wired together so it doesn't matter which one goes where, as long as it's gray. For the others, stick to the original wiring colors; red to red, green to green and brown to brown (or wherever each of these is connected on the original).