The Tennessee Confederate Pension index does not list a J. R. Wallace nor does the Texas index. That is, except for a Joseph Reed Wallace of Smith County, Tx.
As a resident of Texas, this would be the state to which he would have applied for a pension.
Nor do I find a J. R. Wallace or any variant of J____ R. Wallace. Plenty of J____ [nmn] Wallaces in the list of Confederate soldiers in Tennesseans in the Civil War.
George Martin