see if you have one of the 2 listed on cbtricks and look at the modes to make them work on the 148 etc radios. this may help you. I never had one of the 347 counters that had to be modded as you have done this one. do you have a link about the mod you did.
http://www.cbtricks.com/radios/galaxy/fc347/index.htm
http://www.cbtricks.com/radios/galaxy/fc347/index.htm