Just noticed that the N20 model from the shop is a teeny bit off - the various gearbox plates weren’t quite lined up, so you can end up with things being 0.0033mm out and whatnot. Everything is parallel but seems they’re just shifted up/down relative to the motor body.
Probably doesn’t matter for most people but I’m a bit obsessive about things like that, but it could cause issues if you’re referencing off it in a model.
Corrected version here, plus I’ve tweaked a few of the dimensions based on the N20 currently on the desk in front of me (of course YMMV in terms of the exact sizes).