Got a Mustang with the top post keeping locked on. Replaced the TIP122 driver transistor with a TIP102, and also replace the diode on the board. The coil was still locking on, so i traced it to the 50V step up mini driver under the playfield. Swapped it with another on the machine, and coil works as it should. I can't seem to find any info on these boards, was wondering if its likely just needing to replace Q1 or Q2 on these boards. Anyone have any ideas or part numbers worth trying to repair before getting a replacement?

OK, it appears Q1 is the issue (it test differently on diode test to the one in the working board). It is a buk 7240 100a MOSFET, wondering a more common part like a IRL540N or similar that i have on hand could work as an equivalent?