Refitting ZAxis stepper to reduce height

[Rogue]

Hello again everyone :)

I'm moving things around and I thought I'd take the opportunity to make some changes, including finally fitting a Z-Axis to a X2-a-like mill. What I want to do, however, is (i) use belts, (ii) keep the height as low as possible, and (iii) run the screw through the head instead of beside it.

I've roughed out a picture to give you an idea of what I'm thinking of doing. The stepper will actually have a bit of adjustment to allow the belt to be taken on/off the pulley, this isn't shown. In fact the pulley or bearings aren't shown, just the hole to show where they would go!

Any major reasons why this is a bad idea? I don't want to bolt to the front to save those few mm of travel, can't really bolt to the top because the thickness of the walls is around 6mm (some variance), so bolting to the sides is the way forward, assuming it doesn't cause the whole thing to tip over!

Pic shows 20mm alu because... well, just because.

Thoughts or comments gratefully received, as always