Here is step two, wherein I've plugged in my lettering. You can see that in the lower left panel (panel 3) I had originally broken Troy's dialogue over two balloons, but when I was writing it in I expanded what Captain Irons had to say, so I had to compress Troy's response to one balloon.
My original idea was that the final panel would be a silent image. As I post this, I'm still not sure going with the 'for the mound' bubble was necessary. This may be the dynamic of publishing a longer story vs. publishing in serialized form for the webcomic creeping in... I would probably leave that image blank if this was going to be only in a larger book, but since it's going to see life on the webcomic exclusively for the next year or so, and I cannot be sure how recently someone read several pages back when they established their mission objective, I feel like a reminder is in order.