These are the contents of the battery box kit, as well as the two relays (aka contactors). The silver relay is for the battery, and the black one is for the starter.

First step is to cut the eight lightening holes in the (steel) battery box. It's a lot of work, but it's easier with the hole saw than with the fly cutter. Also less scary.

My dad was here to help, but it still took an hour.

Next step was to install the doubler plate that holds the nutplates for the relays. Some of the nutplates go on the angle extrusions.

Then, I had to install the mounting brackets on the battery box. Since the battery fits snuggly in there, the brackets are mounted with flush rivets. All the holes had to be dimpled. Another application for my "close quarters dimpling dies."

These are really cool...I don't know why they don't come in any of the toolkits.

I don't know why photos prove that I built my airplane, but here it is anyway! In the time-honored tradition of homebuilders, here I am holding a tool in the vecinity of an airplane projects, therefore I built it...QED.

After all the hole cutting, drilling, and dimpling, the beatiful powder coat that Van's put on was pretty beat up, so I sprayed a few coats of (gasp) Rustoleum from a rattle can...

...but I needn't have bothered. Most of these rivets were a nightmare to drive, and most had to be drilled out at least once (I'm getting good at that!) By the end, the battery box was looking a bit battered again, but fortunately on the aft side which is not visible once mounted.

Here's the current state of the firewall. I also added the bar between the two relays that carries the starter current.

It more or less fit the way the drawings say, except that the right-hand hole for the battery (left in the photo) did not quite go where the drawing said it should. It's supposed to replace one of the firewall rivets, but it was offset a good 1/2 rivet diameter from there.

Turning to the battery hold-down strap, it starts life as a rectangular 1/8" thick aluminum bar. You first round the edges. Here I am beating the hell out of my Craftsman belt sander. I've replaced the belt once already since starting this airplane. No mercy, I say! Cheap tools were meant to be abused!

Then, seven 3/4" lightening holes are cut. Those take awhile. I made a 1/8" pilot hole, then a bigger 1/4" hole, then started abusing my Unibit untill all seven were cut.

Just missing a couple of coats of primer and paint and it's ready to bolt on! Well, OK, I was supposed to make six holes, not seven, but my "aluminum unremover tool" has not yet arrived. Let's see...the battery weighs 15 lbs, and the airplane is rated for -3 g's, so that's 45 lbs...should be fine.