Implant tools and techniques for implantation of a medical lead, catheter or other implantable component are provided. The implant tools and techniques are particularly useful in implanting medical electrical leads in extravascular locations, including subcutaneous locations. An example implant tool for implanting a medical lead includes a rod and a sheath configured to be placed on the rod. The rod includes a handle, a shaft having a proximal end adjacent to the handle and a distal end, and an attachment feature toward the distal end of the shaft, the attachment feature configured to couple to the medical lead. The sheath is configured to be placed in multiple positions along the rod including a first position in which the sheath does not interact with the attachment feature and second position in which the sheath does interact with the attachment feature.