I had to walk away from this build for a couple of weeks, the fitment (or lack thereof) of the glass was driving me around the bend. The windscreen in particular just would not fit so I ended up having to cut off the locating tabs, re-profile it somewhat then hold it in place while I glued it.
Fitting the engine cover to the rest of the body was similarly frustrating, requiring a small piece of clear plastic which forms the window between cabin and engine bay to be glued to the ceiling inside over the "hinges". Again it didn't fit right and required it to be be held while spot glued.