A system for repairing a defect on at least a portion of an articular surface of a glenoid, said system comprising: at least two guide pins , said at least two guide pins comprising a first guide pin and a second guide pin , said first guide pin and said second guide pin configured to be secured to said glenoid; an excision apparatus comprising a first guide body and an excision device; said first guide body comprising a plurality of guide pin sleeves to contain said at least two guide pins , said plurality of guide pin sleeves comprising at least a first guide pin sleeve and a second guide pin sleeve , the first guide pin sleeve and the second guide pin sleeve being parallel to each other; and wherein, when said first guide pin is contained in said first guide pin sleeve and said second guide pin is contained in said second guide pin sleeve , said first guide body is retained in a first excision position for said excision device; characterized in that said first guide body further comprises a third guide pin sleeve ; and wherein, when said first guide pin is contained in said first guide pin sleeve and said second guide pin is contained in said third guide pin sleeve , said first guide body is retained in a second excision position for said excision device and wherein said third guide pin sleeve is parallel to said first guide pin sleeve and to said second guide pin sleeve , and wherein the center-to-center distance between the center longitudinal axis of the first guide pin sleeve and the center longitudinal axis of the second guide pin sleeve is equal to the center-to-center distance between the center longitudinal axis of the first guide pin sleeve and the center longitudinal axis of the third guide pin sleeve . at least two guide pins , said at least two guide pins comprising a first guide pin and a second guide pin , said first guide pin and said second guide pin configured to be secured to said glenoid; an excision apparatus comprising a first guide body and an excision device; said first guide body comprising a plurality of guide pin sleeves to contain said at least two guide pins , said plurality of guide pin sleeves comprising at least a first guide pin sleeve and a second guide pin sleeve , the first guide pin sleeve and the second guide pin sleeve being parallel to each other; and wherein, when said first guide pin is contained in said first guide pin sleeve and said second guide pin is contained in said second guide pin sleeve , said first guide body is retained in a first excision position for said excision device; characterized in that said first guide body further comprises a third guide pin sleeve ; and wherein, when said first guide pin is contained in said first guide pin sleeve and said second guide pin is contained in said third guide pin sleeve , said first guide body is retained in a second excision position for said excision device and wherein said third guide pin sleeve is parallel to said first guide pin sleeve and to said second guide pin sleeve , and wherein the center-to-center distance between the center longitudinal axis of the first guide pin sleeve and the center longitudinal axis of the second guide pin sleeve is equal to the center-to-center distance between the center longitudinal axis of the first guide pin sleeve and the center longitudinal axis of the third guide pin sleeve . <EOS>