Start where Red Desert indicated. Have you thought about using a two box or your detector with a big coil to verify? If you don't want to draw a lot of attention, make a PVC pipe handle 2' long. I use a Sovereign in a pack bag & this shorty handle setup to search abandoned houses or tunnels that a regular shaft won't fit into. Have you gone far enough to look around where this is? If you can't disturb the front or it hasn't been disturbed what about looking for disturbances on the back side? Take your rods if you have them, spend some time just sitting and thinking how would I? You might be staring at what you're looking for. As mentioned above, black lights are useful in some instances. I modded a battery lantern with longwave & shortwave bulbs. Works great for building searches. Makes wall pendants jump right out at you even under 5 layers of wallpaper. Haven't had any success on rocks or walls. But that doesn't mean it won't work in your situation. Luck to ya!
Being an old temple, besides treasure a person might want to keep safe some old writings or documents, religious artifacts, etc.
We do everything possible, but even then there can surprises...sometimes better unexpected finds or at other times less than hoped for results. Check the 1st pic again, I didn't mark my hit last time, which was about the same spot as Okiedowser found. It will be the red rectangle with the arrow.
