Question:

If you're not familiar, Vanilla Tweaks offers a "3D Chains" pack that uses .json files in assets/minecraft/models/block to make Chains (including the Chain-parts attached to the tops of Lanterns) appear 3D. It reuses the existing Chain textures to create the effect. I'm wondering how this effect could be applied to this mod's Chains and Lanterns (obviously using all the different Chain textures on the applicable Lanterns -- ie. the Amethyst Chain texture on the Amethyst Lantern, etc.). I've had a fiddle around already but haven't been able to figure it out -- the solution's probably really simple and staring me in the face.

The 3D Chains pack can be found at https://vanillatweaks.net/picker/resource-packs, under "3D" (I'm trying to do this in 1.20.1 in particular, but any solution would most likely work across versions I'd assume).

I've attached some screenshots showing the effect applied to the default Chain and Lantern in comparison with two regular 2D counterparts.

This is purely out of curiosity and for fun! Absolutely no rush/pressure/etc.. The mod itself is epic regardless.

Here are the three models used for the lanterns by Additional Lanterns: https://github.com/SuperMartijn642/AdditionalLanterns/tree/forge-1.16/src/main/resources/assets/additionallanterns/models/block.
They pretty much just correspond to the ones vanilla uses. You'd have to overwrite those models with a resource pack, the same way Vanilla Tweaks overwrites the vanilla models.