Here are some pictures of  how I permanently mounted my Battery Maintainers.

I attached the Maintainer to a fender support
using plastic wraps, then connected the negative wire to the car frame and the positive wire to a post in the red junction box.

I secured the AC cable with plastic wraps, threading it down to below the front bumper and made a wire hanger to store it on when not in use.

Make certain the cable does not dangle when the car is moving. You don't want it contacting the tire or the road. If not done right, you might surprise yourself with an air bag deployment if the cable should snag something. 

Here's a close up of the maintainer, securely installed, under the hood.

The block of foam is to cushion the maintainer from contacting the car body

Here, the orange AC cable is connected to the black Maintainer  cable. It is positioned to be shielded from rain and I wrapped a heavy plastic tape in the shape of a cone around the socket to further shield the connection.

I printed a card with: "Do Not Move Car Without Disconnecting the AC Charging Cable." 

That card is positioned in front of the speedometer every time the car is connected to the AC cable. A driver can't see the instruments without seeing that message first.

The Oldsmobile Installation
Below, the Nissan installation is similar to the Olds installation. Find a safe and secure place for the Maintainer, add your wires as needed and don't forget to print a "Remove Cable" card to warn drivers. 
The Nissan Installation

I already had AC power to my outdoor shed. I control that power with an in-house switch which controls a duplex receptacle in the shed, so all I needed was a couple of outdoor extension cords to run from the shed to the vehicles. I usually  allow the Maintainers to run a few hours every day, then switch them off at night.  Actually there is no need to turn them off, ever, but it pleases me to announce to my wife: "I'm going to do some mechanic work" then I flip the switch on or off, ha ha. I make a daily game of it.

I found a safe place to mount the Maintainer between the battery and the front support. It is a perfect fit.
The next page is professional tips about maintaining batteries.

WARNING: Batteries are dangerous.
Read my warning at the top of page one.

Page 2,
Page 2 of 4.