How to use these Romsets with your PCB:
Your Sengoku Ace PCB should have 3 Eproms on sockets. 2 of them are relevant for swapping the revision; the ones at position U126 and U127.
Replace them with a new Eprom set. To create a new eprom set, take the 2 Rom-Files from the zip archive you downloaded from here and burn them on new Eproms of the same type using an eprom programmer. It should work by reburning the old Eproms too, if you properly erase them first.
hints: A useful method to remove an eprom from a socket would be to stick a flat screwdriver between eprom and socket and then to rotate it carefully until it lifts both sides of pins out of their slots. Always keep an eye on the correct direction whenever you place a eprom into a socket (Look out for that small gap at one side of the chip. Find the same gap imprinted on the surface of the PCB)