I was looking into the board revisions. My B-Board is a 91634B-2. I found the following under punisherj which also uses this board:
ROM_REGION( 0x400000, "gfx", 0 )
ROM_LOAD64_WORD( "ps_01.3a", 0x000000, 0x80000, CRC(77b7ccab) SHA1(e08e5d55a79e4c0c8ca819d6d7d2a14f753c6ec3) ) // == ps-1m.3a
ROM_LOAD64_WORD( "ps_02.4a", 0x000002, 0x80000, CRC(0122720b) SHA1(5f0d3097e097f64106048156fbb0d343fe78fffa) ) // == ps-3m.5a
ROM_LOAD64_WORD( "ps_03.5a", 0x000004, 0x80000, CRC(64fa58d4) SHA1(d4a774285ed15273195b6b26d2965ce370e54e73) ) // == ps-2m.4a
ROM_LOAD64_WORD( "ps_04.6a", 0x000006, 0x80000, CRC(60da42c

SHA1(95eec4a58d9628a2d9764951dd8dc11e4860a899) ) // == ps-4m.6a
ROM_LOAD64_WORD( "ps_05.7a", 0x200000, 0x80000, CRC(c54ea839) SHA1(0733f37329edd9d0cace1319a7544b40aa7ecb0b) ) // == ps-5m.7a
ROM_LOAD64_WORD( "ps_06.8a", 0x200002, 0x80000, CRC(04c5acbd) SHA1(fddc94b0f36d4d22d7c357856ae15b7514c342d3) ) // == ps-7m.9a
ROM_LOAD64_WORD( "ps_07.9a", 0x200004, 0x80000, CRC(a544f4cc) SHA1(9552df8934ba25f19a22f2e07783712d8c8ef03c) ) // == ps-6m.8a
ROM_LOAD64_WORD( "ps_08.10a", 0x200006, 0x80000, CRC(8f02f436) SHA1(a2f0ebb7e9593469c7b843f8962a66f3d77f79e5) ) // == ps-8m.10a
If using the world romset, does this mean the graphics chips preceded by "//==" go in the position of the ones in quotes? Sorry if this is a dumb question. I'm trying to troubleshoot.
EDIT: I reprogrammed the GAL chips, and now I get a quick flash of graphics on the screen when powering on. I don’t know if this is a step in the right direction or not…