I went through the same thing you are. different ways of doing it. I settled on (long time ago) removing the top to look in and I then pushed in the new upgraded tensioner and while unscrewing the old one I kept some tension on the chain. I screwed the new one in and then used a long screw driver and tapped the tensioner pretty good and it popped out. BUT to be honest before I read anything on it I took the old one out just unscrewed it looked at it and cleaned it and just put it back and started the motor and all was fine. except the tension was not working and I had a bad knocking sound. I then put in the required amount of SEAFOAM in the oil and my boy called me got on the phone and talked for about 10 min away from the 68 ecotec powered Baja Bug. came back and all the knocking sounds were gone and all was nice. Still changed out the tensioner. and have beat the heck out of the motor many times in the desert its on its way back from 100 mile beating today. The engine seem bullet proof.