This is where MAWS comes in handy. You can look at the different revisions and see what chips are different.
MK 4, Rev 2.1:
http://maws.mameworld.info/maws/romset/mk4a
Code:
roms name size crc set flags sha1
mk4_l2.u2 1048576 f9d410b4 mk4 49bcacf83430ed26c08789b2f3ed9f946c3a0e5e
mk4_l2.u3 2097152 8fbcf0ac mk4 c53704e72cfcba800c7af3a03267041f1e29a784
mk4_l1.u4 2097152 dee91696 mk4 00a182a36a414744cd014fcfc53c2e1a66ab5189
mk4_l1.u5 2097152 44d072be mk4 8a636c2801d799dfb84e69607ade76d2b49cf09f
mk4_l2.1.u10 2097152 42d0f1c9 mk4a 5ac0ded8bf6e756319be2691e3b555eac079ebdc
mk4_l2.1.u11 2097152 6e21b243 mk4a 6d4768a5972db05c1409e0d16e79df9eff8918a0
mk4_l2.u12 2097152 7816c07f mk4 da94b4391e671f915c61b5eb9bece4acb3382e31
mk4_l2.u13 2097152 b3c237cd mk4 9e71e60cc92c17524f85f36543c174ca138104cd
mk4_l2.u14 2097152 fd33eb1a mk4 59d9d2e5251679d19cab031f51731c85f429ba18
mk4_l2.u15 2097152 b907518f mk4 cfb56538746895bdca779957fec6a872019b23c3
mk4_l2.u16 2097152 24371d57 mk4 c90134b17c23a182d391d1679bf457d251e641f7
mk4_l2.u17 2097152 3a1a082c mk4 5f8e8ce760d8ebadd1240ef08f1382a37cf11d0b
MK 4, Rev 3.0:
http://maws.mameworld.info/maws/romset/mk4
Code:
roms name size crc set flags sha1
mk4_l2.u2 1048576 f9d410b4 mk4 49bcacf83430ed26c08789b2f3ed9f946c3a0e5e
mk4_l2.u3 2097152 8fbcf0ac mk4 c53704e72cfcba800c7af3a03267041f1e29a784
mk4_l1.u4 2097152 dee91696 mk4 00a182a36a414744cd014fcfc53c2e1a66ab5189
mk4_l1.u5 2097152 44d072be mk4 8a636c2801d799dfb84e69607ade76d2b49cf09f
mk4_l3.u10 2097152 84efe5a9 mk4 e2a9bf6fab971691017371a87ab87b1bf66f96d0
mk4_l3.u11 2097152 0c026ccb mk4 7531fe81ff8d8dd9ec3cd915acaf14cbe6bdc90a
mk4_l2.u12 2097152 7816c07f mk4 da94b4391e671f915c61b5eb9bece4acb3382e31
mk4_l2.u13 2097152 b3c237cd mk4 9e71e60cc92c17524f85f36543c174ca138104cd
mk4_l2.u14 2097152 fd33eb1a mk4 59d9d2e5251679d19cab031f51731c85f429ba18
mk4_l2.u15 2097152 b907518f mk4 cfb56538746895bdca779957fec6a872019b23c3
mk4_l2.u16 2097152 24371d57 mk4 c90134b17c23a182d391d1679bf457d251e641f7
mk4_l2.u17 2097152 3a1a082c mk4 5f8e8ce760d8ebadd1240ef08f1382a37cf11d0b
Looks like the difference is U10 and U11. You'll need to replace 2 chips.
If you can get me the #s on those 2 chips that are under the labels I'll see if I have some that I can program for you.
RJ