So coming up through the bottom of the top grate is not working for you ?Its perfect for the bottom grate in my opinion but I use a grommet for the top grate for now, prob gonna notch it as the notch is very convenient.
Good idea to identify the plug ends.I like it. Like Terry said, remember to thread the wires before you put the two sections together.
One other thing I did was I tied a bread tie to the plug end of my food probe. This is so I don't confuse the two probes. One of those quick things to do one time that makes it a little easier to set up.