[wasayanwer97]

V3 is looking good!

A few things though:
1. To make facemounting easier, I would go one of a few routes: Put the four bolts holding it together in through the back and tap the front plate (this would give you a flush, flat front) or I would use countersunk bolts on the front instead. The other option is to just have holes for the bolt heads to fit through on the spot you're mounting this. Generally, your mount will be a lot more snug and reliable if the face is right up against the surface you are mounting it to.

2. You probably already know this, but just to remind you, you're going to need another spot for a bearing on the front plate if you intend to add a third stage.

This is a beautiful, elegant gear box. Awesome job on it!