Happy, the radio antenna wire should run down thru drivers side A pillar. If you mount you CB antenna on the A pillar you should be able to pass the wire down the same path. Easiest way is to remove inside trim and use coat hanger to fish the cable down under the dash, I've done it this way 5-6 times on our coaches and for friends.
Dave & Myra
One day your life will flash before your eyes,
make sure it's worth watching!