The SMB manual is giving the typical location of standard group 27 battery(s).
The large battery under the van on the passenger side is the optional group 4D house battery. If your van is diesel, there is a smaller battery in a steel enclosure forward of the 4D house battery, this is your second starting battery.
The group 4D battery SMB uses does have "L" terminals to allow easy installation of the battery cables. This AGM battery is virtually maintenance free. The Battery you currently have is most likely a Lifeline brand. You can also use the same size MK or DEKA AGM battery with the same "L" terminals and save many dollars. Visit their websites to find a dealer near you. http://www.mkbattery.com/locations.php
The 4D battery weighs about 135lbs. The careful use of a floorjack is the second best way to remove and install a new battery. The best way is to have a service garage perform the job! Make sure whoever does the job runs a bead of Sikiflex or similar sealant around the battery at the top edge of the angle-iron cradle. This will help keep small pebbles from finding their way between the battery case and the angle iron frame and also helps to secure the battery to the cradle.