Hello, thanks for the advice.
I did have a go at cloning a deco mesh, then replacing the GMDC (the textures of the CC counter are repositoried to the base game Moroccan wardrobe), I followed this tutorial here
https://modthesims.info/showthread.php?t=399438, although I found it a bit difficult, because it's aimed at making your own object from scratch, which I have never done before (I have used Milkshape years ago, for shoe swaps etc.). I ignored the parts of the tutorial about creating your own mesh and textures (skipped Step 5 to Step 7, just carried on with Step 8 onwards. But I went wrong and just ended up with a recolour of a Maxis object.
I have done lots of clothes and hair defaults, but always used either the method of replacing the GMDC, GMND, CRES and SHPE and textures (I call that a Mesh DR), or the method of replacing the GZPS and 3DIRs and textures (I call that a Property Set DR).
I have DR'd a few objects in my game sucessfully using the Mesh DR method (like for like though, eg. single bed replacing single bed), so I'm comfortable with that.
I've never done the DR method where people only replace the GMDC, I'm a bit baffled by how it works. I never found a tutorial for it.
So for now, I think that might be beyond my skills, but thanks for suggesting it anyway.
I think the other option you suggested might be best for now, of using deco items or a slot blocker (I have one already that I used for something else), so I'll do that for now, thanks for your help though

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