Donkey Kong 4 Board Identification

[Guss]

Anyone familiar with DK 4 boards?
Looking at a 4 board set that has Nintendo 1981 branding.  One is labeled "TKG-SOU". (see pic)  No numbers.  Board below it is labeled "TKG-CPU" above the bottom "F" and "G" section markers.



I'm curious if this is a rare board set. No mention on dkforums rom listing.  http://donkeykongforum.com/index.php?topic=439.0

Owner says its all original, thinks cabinet is pre-production machine.  (I think it's just a DIY job) Almost a Nintendo looking cab on the outside. Particle board sides with wood vinyl look, square coin door, no monitor support brackets on cab walls, Kaga chassis, Mitsu tube, boards mounted on right hand side. No Nintendo Power Supply, looks like a Happ style. (doesn't look like the standard Nintendo configuration)

Board label is curious tho... is this a standard cocktail board set maybe? Bootleg? Japanese version? or really a pre-production TKG board?

"Why is this Cab Brown!"

Thanks

[iankellogg]

It would be nice to have a better photo of the entire board to do proper comparisons.

[yocke]

My DK 4B set says

Soundboard
TKG-SOU

CPU board
TKG-CPU

Videoboard
TKG-VIDEO

Lastbboard,
dont say much!? Strange!

All boards have "NINTENDO 1981"

If you have better pictures, we can compare!
 ;)