Third, if your replacement ROM's are similar or identical to your old ones, mark the old ones with a small dot made with a felt tipped pen. This will prevent mix-ups between new and old. Carefully remove ONE old ROM and replace it with the new one. Repeat for the other one (if firmware only) or the other three if doing firmware and Tone Generator ROM's. Also shown below is the location of the lithium backup battery on the EX5 (it's under the case lip, the next picture shows it more clearly) and the SCSI termination switch on the ASIB1 SCSI interface. Note especially the orientation of pin 1 of the ROM's. Some tips on ROM fitting are shown at the end of this document.