Rebuilding Ancient Indian history is not unlike the science and techniques employed by Dendrochronology.
A powerful analogy (but only an analogy)
In case of ‘Ancient Indian history’, overlap of ‘fingerprints’ won’t come from different trees, but rather from records of different disciplines viz.
Records of recent history – epigraphs-reference events/astronomy events mentioned in epigraphs and other records – References calendars -Ancient Indian narratives (Mahabharata, Ramayana, Samhitas, Brahamanas, Sutras, Puranas, etc.) – hydrology-seismology-oceanography -climatology-dendrochronology-paleontology-eclipsazoology-geology-astronomy-genetics-archaeology-cosmology….
You get an idea.