Originally Posted by Beau388
If there is space in the original battery compartment for the batteries, I would assume the battery compartment is stressed for the load.
There is space, but just barely. There is (was) a sliding tray that holds three 12 volt batteries. But the years had taken their toll and it was rusty and nasty looking. I was going to clean it up but opted not to. Instead, I laid a 1" thick rubber mat in the compartment and then welded a brace under the compartment. (Probably didn't need the brace but I did it anyway.) With the tray out of the way, there was room for the four batteries I placed in it.