Well, the install went pretty smoothly. The only hang up were a couple of leaky joints, nothing a wrench couldn't fix though.
Here is what I started with.
Here is the puddle, notice the glassy reflection of the bags in the background, all wet. I had cleaned it up several times already too.
This board right in back of the water heater holds my hydronic heating pump, control, gauges, etc. I figured I would just add on to it for mounting the water heater.
With the extension added, two screws hold the water heater to the board. The wire is some pretty beefy 8-2 wire. I had to add a 50A breaker to the electric panel as well.
Then, I installed the ball valves, and servicing valves (for flushing the water heater).
The last thing to do was connect the PEX lines which was a very short run. I ended up getting one of the cinch crimping tools that AC Hacker suggested some other thread. It really worked nicely.
After it was all done I decided to clean up and test it out. The water temperature is absolutely perfect. I'm glad I didn't go with the next size up.