I trimmed my 1990 rev. SNES board to be quite small, I believe. Its the early revision with the sound card board that you have to plug in. I removed the S-ENC chip, so there is only RGB video available. I cant test it yet, but I will let you know if it works as soon as I can. Pictures!!!!!
Small schematic I came up with

Its about the size of a DMG

RGB video soldered to PPU2 chip
