There is a pin that locates the timing chain rail. It is what is most likely holding the cover. I typicaly remove the pin before the cover. It is located behind the 5mm allen plug under the cam adjuster. It is removed by pulling. You can pull it with a bolt, nut, and socket. Screw the nut all the way onto the bolt, place the bolt through the socket and screw it into the pin. As you hold the bolt unscrew the nut, which should start to pull the pin once the tension builds. With the pin removed the cover should come off relatively easy.

The cams lining up 5ATDC is normal for the mileage on the engine. It would be a good idea to replace the timing chain while you have it apart. That should bring the timing back closer to 0TDC although if you have the head milled it will retard the timing a degree or two but will not be of any consequence.