The May 09, 1882 issue of The Waco Daily Examiner shows a J P Gatewood as owning 30 acres of land in the Tomás de la Vega tract, which would place it in East Waco, near the Brazos river (land that became the future home of Bellmead, TX along State Highway 31). This information also appears in the McLennan County Supplemental Tax Rolls (1878 -1888) Archive at:

http://www.co.mclennan.tx.us/arc/taxrolls.aspx (see the .pdf for 326-350 closer to the bottom of this page - his record is for 1881)

I hope this provides to be a decent lead, and hopefully the right J P. I'm not seeing many Gatewoods on the McLennan County taxrolls around this time.