During implant of an implantable medical device, implanted cables or leads are inserted to a connector block. An insertion indicator provides the user with a visual indication the cables or leads have been correctly inserted into the connector block, which enables the implanted medical device to properly deliver treatment or receive signals via the implanted cables or leads. The insertion indicator may be provided by a mechanical indicator optically viewable once the lead has been correctly inserted, and/or may be provided by an electrically activated light indicator illuminated by a power source associated with the connector block or with a connector tool used to connect the lead or cable to the connector block upon correct insertion of the lead or cable. The insertion indicator may be permanently or removably disposed on the connector block, a connector tool, and/or a can associated with the connector block.
