The only issue I ran into was the actual side panel (the final piece of the puzzle to remove) wouldn't come out easily. It is wedged under a lip of metal on the top of the battery casing in the back corner right behind the seat. I had to essentially 'rock out' the panel from the top. This is different than what the WSM suggests sliding it straight out.
Other than that, the rest of the process was straightforward. Once I was able to get the side panel off, I basically followed the same exact instructions laid out in the CSP for the TCU installation including placement, use of velcro strips, etc.. Since the DIY modules are essentially identical to the official ones, that process is no different.
EDIT: As an FYI for the thread as a whole, I'll work on updating and cleaning up the initial post of the thread with the new and relevant info we have so far. Will try and get this done in the next day or two.