Yes, many American cars have a simple spring loaded tensioner that is loosened with a bar. Very simple.

Unfortunately the M103 tensioner is more complex, but not too bad. There is a damper that usually doesn't need to be replaced and a tensioner with the pulley on the arm. This is the part that typically needs replacing.

You should first loosen the big bolt through the middle of the tensioner, then see if the pointer is at smallest point of the inclined plane shaped marker. If the tensioner will not tension to the narrow part of the marker, then the tensioner is probably bad. You really would be best served by getting a manual or CD that will have illustrations.

Good luck,