Thanks to Henry Ching for these notes:
The Wing Pit Ting Pavilion was on Pokfulam Road, on the right hand side going up the hill towards the Queen Mary Hospital. It was on the outside curve of the road immediately past the University sports ground, south of and overlooking the old University sports pavilion in the south-east corner of the ground. The curve disappeared when Pokfulam Road was widened and put straight through to the south.
The original line of the road is still there - it runs past the sports grounds and playground. So I've put the marker about where the bend Henry describes was. That location also matches Thomas's estimate that the pavilion was opposite where the boundary stone is:
http://gwulo.com/node/13700#comment-24025
Regards, David