I also knew that I would have to drill a hole in the floor and install a 50 AMP plug which would also be wired to the electrical system. Here are some pictures of the other end of the 50 AMP plug after I pulled it into the closet area of the cargo trailer.
Another friend of mine named Shane F. Helped me out by loaning me a pair of heavy duty crimpers, and a pair of heavy duty cable shears. Shane also gave me the necessary lengths of 1/0 & 2/0 copper wire. There is no way I could have accomplished the process of wiring up the batteries this quickly without the help of both of my friends Shane F. & Shane O. Thanks guys!
There are some pictures of the wiring of the battery charger, the batteries, and the connection to the outside. There are also pictures of the many tools and materials I used to accomplish the task.