This is exactly what I was hoping for just a couple weeks ago. I've been playing through IR3, and easily the single biggest game changer it provides is the mini assemblers that only allow those single ingredient recipes, and that has made builds so much more fun and unique. I haven't installed this yet, but have been imagining something like this for a SE+K2 playthrough. I'm about 3/4 the way done with IR3, but I'll definitely be installing this when I start my SE + K2 playthrough. I'll let you know about any potential compatibility issues (hopefully it's compatible). Thanks again!

Glad to help! I was also missing those sweet 1x1 assembling machines and while I was mostly satisfied with other mods' implementations, I specifically wanted them to respect the recipe rules of e.g. AAI Industry (used by SE). On that note, I've actually just finished and confirmed support for both SE and K2. Let me know if you run into issues when you get to it!

I didn't test SE+K2 combined, but K2's custom assembler is a 5x5 and doesn't have any unique 1-ingredient recipes anyway, so from my inexperienced perspective, I'll leave that one untouched in its massive glory. Same thing with the giant space manufacturer from SE. If you think either does warrant a mini version of some variety (I could investigate creating maybe a 2x2 or 3x3 "tiny-in-comparison" version without it looking too silly... but I think that goes against the spirit of those buildings, and I'm guessing the tier-below assemblers may work just fine as the assembling machines for simple intermediate parts)