Hey Dreamseed!
Glad you like it!! I didn't make it for the Jam, but did do a little bit of modification to the shader to actually get it working on godot 4.1 and then also just to get it dialed in. You can find the shader here:
https://godotshaders.com/shader/ps1-post-processing/
This was also a great resource for other shaders I messed around with but didn't end up using:
https://github.com/MenacingMecha/godot-psx-style-demo
What I used was a bit of the PSX-lit from the github link on models in the game and then post-processing with the first link to get the dithering :)