I just swapped out my 5 inch convex mirrors for the 5X7 rectangular. On the right side I put a small adjustable convex for complete coverage. The rear view is much better now, especially when backing.
A long time ago I had some of the smaller west coast mirrors on a 41 half ton. As I remember, they looked great and gave me panorama of rear vision.
Als good to rest your hand on when driving around.