The present application describes an implant system useable for positioning an implant device such as a device useful for restricting passage of ingested food into the stomach. In one embodiment, the disclosed system includes a plurality of anchors that may be coupled to tissue within the stomach, or to a tissue tunnel formed by plicating stomach wall tissue. The anchor includes a loop. During use, the implant device is inserted through the loop and expanded such that it retains its position within the loop until removed. Instruments for implanting and explanting the implant device are also described.