I'll answer my own question. The tab at the top of the electrical connector to the crankshaft position sensor pushes in, to lift the retaining plastic insert up and over the little upraised piece on the sensor itself. Of course, it barely moved due to age. So i removed the sensor itself (it was stuck too), and pulled it out and positioned it as to get a view of the part that should have lifted up for release. I got a miniature flat headed screw-driver and pushed it under the connector's retaining piece and lifted it up and pulled the sensor off. I lightly put some silicone lubricant on the sensor's placement hole in the aluminum mounting by the crank and even had to tap the sensor in to get it to bottom out. I accidentally pulled the wiring protection tubing from its insert on the plastic electrical connector, so i just wrapped duct tape around it for dirt and water protection. The biggest issues are very tight quarters in which to work and stuck components Some people claim there are horizontal 90 degree flat tipped pliers made specifically for depressing these types of release mechanisms, but I didn't want to run around looking for them.