This WWF Wrestlefest board worked fine apart from vertical lines across the screen.
I went down the rabbit hole with this one first thinking it was most likely one of the surface mount custom chips as there isn't too much else on these boards. I fixed a couple of loose pins and took off the TJ-003 custom chip as it was so badly fitted at the factory that the top row of pins were almost touching the wrong pads by less than 1mm.
This made no difference though, I then went on to use a couple of different community made test roms that test the rams but these all passed. The problem with these test roms is they tell you they're testing background / sprite etc rams but not the locations and more importantly the ones they don't check.
Turns out they don't check IC24, 26 and 27, I guess as they don't have direct access to them from the cpu and as these were the main rams I suspected of being faulty I decided to just remove and test them.
Luckily the first one I removed (IC24) turned out to be the bad one, a standard 6116 skinny type. I fitted a socket and a new old stock ram and it's back up and running as noraml.
Bad Ram
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