How can I separate one latent into 3 that will be used as a batch?

[Extraltodeus]

I figured how to put a batch together as one but I can't seem to get how to crop one latent into 3 parts that will become a batch.

I'f you're curious:
I'm doing triple monitor wallpapers so my idea would be to generate a smaller version -> crop it into 3 parts piled as a batch -> upscale the latents -> sampler go brrrr -> stitch back as one -> last lighter sampler pass to weld them together.

So far I've been able to make a batch of 3 and put them all as one but if I try to split a latent space I get weird stuff.

The docs are here : https://blenderneko.github.io/ComfyUI-docs/Core%20Nodes/Latent/batch/RebatchLatents/

But...

To be clearer:

The concat latent node is one of my attempts but it does not work. Any idea on how to do such thing?

[Extraltodeus]

well... My main issue was to crop into 3 parts a latent with a width of 1512 instead of 1536 which was making impossible to concatenate since divided by 3 would have different sizes...