Not sure if this of any use to any of you lot but just been messing skinning the StadiumCircuitBase model from here and found if you skin it the same as block 7-2-3-6 in bay and put it in water it looks like this.
One is the model that I skinned and the other is the block. Not 100% but would fool people in a track
Yes it's Bay block 7-2-3-6 and it can be skinned to look like Bay block 7-2-3-7 to. The StadiumCircuitBase model sits very nice in the water next to them.