This invention relates a modular surgical kit for repair of diseased cartilage at an articulating surface of a joint. The modular surgical kit is for use with a medical implant (10), a grafted plug (600) or an artificial plug that has an implant body (27, 627) with a predetermined cross-sectional profile (81). The modular surgical kit comprises a guide base (12) that has a positioning body (11) and a guide hole (53). The surgical kit also comprises a guide body (13) with a guide channel (54). The guide channel (54) has a cross-sectional profile that is designed to correspond to the cross-sectional profile (81) of the implant body (27, 627) and also has a muzzle 32. The guide base (12) further comprises means for releasably connecting (47) to the guide body (13) such that, when connected, the guide channel (54) is such that its muzzle (32) emanates at a site corresponding to the site of implantation into the bone.