Tirupathy Perumal appears to be combination of Narayan - Sankara and Sakthi!
Thirupathi Ezhumalaiyan Penn Deyvama ? By Suba. Venkataraman, (80 yr old) Oliver Rd, Mylapore, Chennai has brought out interesting details in his book.
Since this book deals these aspects - let me confine - re Thirumala as the Sacred Divyadesam hymned by about 10 Azhwars .. !!