58 coupe heat problems

I just bought a 1958 coupe de ville, it's in pretty good shape, but it has a few small problems. The mufflers are only about 1/2 inch from the floor sheet metal. Is this correct? Also, one of the brake lines runs about 1/2 inch from the exuast manifold on the drivers side. Seems like this could cause brake loss. Am I right?
This model seems to have come without a radio installed. Was this an option back then? Thanks, Larry