[David]

I have never worked on a 38-4 but will try giving you some ideas to work with. A simple long wire in the attic can take pvc pipe or fitting to make insulators.  Second would be a dipole, insulator in the middle of the ant wire and two leads going to the radio. I have a long wire in my attic total length 30 feet happy with the results. Work shop one ant is a piece of wire app 20 feet long under a over hang some what directional. The wire can be something as small as 18-20 gauge in a attic. David