I replaced my rear calipers and hoses (rear) while I was at it. I also replaced the hard lines. The old steel ones made me a little uncomfortable upon inspection. I put in nice new pre-bent SS lines. Of course they didn't fit perfectly, so a little bending was in order. Everything works fine but the new lines make contact with other components (lightly) in a couple of places. One barely touches a trailing arm and the other touches a caliper. Should this concern me?

if you cannot reposition the lines so they will not touch you might be able to cut pieces of rubber hose and put over the lines to keep them from chaffing.

Eventually they will start to rub. I say use duct tape!! Lot's and lots of duct tape. Or rubber hose or try to give a little bend or move the clips.

Wait..wait... Are you suggesting I pull a Bubba? Smile...

Are you saying your hard lines are rubbing, or the soft lines that connect to the caliper?  The hard lines shouldn't be anywhere near the calipers.

Hard lines are very near the calipers. About 1/8 inch. I did install some rubber tubing to make sure there is no rubbing.