With the help of the 1892 Williamport Directory and a lot of time this morning, I found 1510 Scott Street in the 1900 census on Ancestry.com. It shows up in District 94, image 3 of 38 and household 28/29. I am having difficulty reading the names but you may be able to figure it out.

If you can figure out the surname, then check the 1910 census to see if they are still at that address.