This 3rd Armored Division History Foundation [ 3d / Third ] in COMPLETE TEXT of "SPEARHEAD IN THE WEST" 3rd Armored Division's 260-Page WW2 History - Published in 1946 says that 703rd Tank Destroyer Battalion was at Mere.
There is a plaque to a US armoured division (I think 3rd Armored) on a bridge in Longbridge Deverill, a few miles from Mere. Photo to follow.
This is the Longbridge Deverill plaque. Had hoped it was going to mention the recon battalion but it appears to be the same as the Mere plaque.