There seems to be no acknowledgement of the simple mosaics in this area, but they seem to have been done by a local school for the 150 year anniversary of Seymour in 1994.
To find the final you need to grab a few numbers from the tiles.
Jennifer Smith's tile (with turtle) has two numbers AB.
Mullin (Golden State Warriors) #CD
The Seymour Football Club (Simon's tile - a double tile) has only two numbers EF
Seymour Lions (simon's other tile) has stacks of numbers, we are after the pair to the left of the lion's head GH
Shaun Kemp (basketballer) number is JK
Dominique (a Atlanta Hawks supporter) LM
The cache is at: S37 03.(C+H)(D+E)(F+J) E145 06.(A-D-G)(E+L)(B+L+K)