Here is a Google aerial view of K-99 in Howard. That is Toots Drive In in the upper left.
(http://i941.photobucket.com/albums/ad256/waldoegray/sun%20street_zps9ifcwp4t.png)
Another view
(http://i941.photobucket.com/albums/ad256/waldoegray/sun%20street_zps9oetfnts.png)
Is that an anomaly in the photo or is/was there such a street?
I believe that is just an anomaly. I can find no plat or land parcel map that shows there ever having been a street there.
This is from Delorme Maps. It shows Sun Street closer to Randolph than Adams.
(http://i941.photobucket.com/albums/ad256/waldoegray/Sun%20street%20II_zpszhmh8nnb.png)
This is what I found when I did a search for "Sun Street, Howard, Kansas"
(http://i941.photobucket.com/albums/ad256/waldoegray/Sun%20Street%20III_zpsmm9dhocw.png)