After weeks spent to test A LOT of AMD 486 with the Universal Chip Analyzer, messing with a gas torch to decap some of them and speaking with a former AMD engineer that worked on them back in the 90s, I’m happy to publish here all the information I was able to get! Here it is:
The Ultimate AMD 486 Die & Packaging Guide
PS: If you have any more information about AMD 486, please leave a comment. Thanks!