found this with my search fu, looks like youll need to change the yoke too..
"Call the parts department at Wells-Gardner (1-800-336-6630 or
708-290-2100) and order one of Service Kit # S02J0000-000F U5000 to
K7500 kit. This includes main board, neck board, remote adjust board,
yoke, and transistor assembly. You cannot reuse the old U-5000 yoke as
the k7500 yoke is different. "