Hi, thought that I would post my progress to this point installing the 2 6-volt batteries. These AGM's weigh in at 90# each. I called Keystone and they recommended that I reinforce the floor of the battery compartment to support the weight of the batteries. I added angle along the back wall, the outside I-beam gave support of the outside line and the crossmember from the generator prep is providing support to the inside edge though I added angle between the tabs. I put a 3/4" plywood floor covered with aluminum. The floor is secured and to this point I have the batteries in, base frames for each battery are loose in place. I will finish in the morning by screws securing the angle around the base of the batteries.
Picas web album of floor/battery installation