WOWWWWW!!! Awesome stuff! Thank you a lot for these pieces of artwork Mr.DO! They have much better resolution than I thought they would have coming from a collection like this. Now I'm convinced that this SNK 40th Anniversary Collection is for real!!
Here's a similar artwork I found on Twitter some time ago, it looks like the original ones you posted here, but in a different displacement:
I think it could be an earlier draft of these final instruction cards that came out with the original kit. Maybe the SNK collection has some info on this one as well.