Avs Fan

Hello. I've been reading this thread for a while but still don't find something, that can help me in my problem. I have JDM Legacy B4 GT 2005 with Kenwood GX-203JEB 6-CD changer audio. I need to convert japan frequency range (76,0-90,0) to european (88,0-108,0). Does anybody know how to do it correctly or may be have 203JEB service manual?