TKG3-07 using US Set 1.
Replaced 3 EPROMS on the CPU board:
5F, 5H, 5K
It behaved just like US Set 2


Then tried roms individually.

EPROM in 5K changed to Set 2.
screen freezes in the first attract screen before Jumpman makes it to the first ladder.

EPROM in 5H changed to Set 2.
(c) 1981 Nintendo of America Inc.
Ladder trick is available.

EPROM in 5F changed to Set 2:
(c) 1981 Nintendo of America Inc.
Ladder trick is not available


In pairs:

EPROM in  5F + 5H changed to Set 2:
(c) 1981 Nintendo of America Inc.
Ladder trick is available.

EPROM in  5F + 5K changed to Set 2:
screen freezes in the first attract screen before Jumpman makes it to the first ladder.

EPROM in  5H + 5K changed to Set 2:
Screen freezes at the title screen. The screen is black with 'Donkey Kong' in Red.