I had up to stage 3 done at some point but I can't seem to find that file. I'll just leave this up in case anyone wants to try and do an improvement for this in the future.
#638399106951255897 - Mickey Mania 28 frame save
Mickey Mania - The Timeless Adventures of Mickey Mouse (Japan).bk2
Just uploading this here so if someone in the future needs to use it.
Submission coming soon.
edit: should note this bk2 was used on an early version of the bizhawk dolphin fork that doesn't include certain inputs (resets iirc). It'll have to be fixed before it can be replayed by anyone, apologizes for the inconvinence