Location
Hill 27 is located at "The Gifu".

Peter Flahavin reports:
"The Japanese lost about 100 men in the Hill 27 battle and I think most of them have been dug up by the Japanese and cremated at their memorial on Hill 27, but bones can still be found in the ravines."

Japanese War Memorial to "Oka Force"
The Japanese have constructed a simple white pillar memorial to the Oka Force that died here. Nearby was a pile of shrapnel and more Grand rifle clips. [Read Memorial Plaque]

References
Thanks to John Innes for additional information.