Ok so MAME says 19xx uses a combination of 4mbit and 16mbit mask ROMs in alternating sockets and 16mbit sound ROMs in sockets 11/12
13 - 4mbit
14 - 16mbit
15 - 4mbit
16 - 16mbit
Can you confirm it was an E PAL? I’ve never seen an E before and F sounds correct because it’s running 16mbit...