From what I understand, the smaller battery is used only to keep "essential services" running when the car stops - it's the main battery that does the heavy lifting for starting. If the car determines that the smaller battery won't keep things alive, stop/start is disabled. The underhood points are for jump starting the car and exist even if there's no smaller battery (as on later models).

 

I decided not to use the Comfort Indicator Panel option as I didn't want to try and pull the interior panel to fish the wires behind it. But a problem arose trying to use the pigtail with the ring connectors that came with the CTEK. It is a few inches too short to come out once the storage compartment is put back into place. I'll have to see if CTEK has a longer pigtail and order that one.
Thanks for everyone's help.

 

The connector I have is 58cm (just under 23") from tip to tip. It's not the one that came with the charger.

 

The connector that came with the charger is their part # 56-260 and has the M10 ring lugs. They do offer it as an accessory with your choice of M6 and M8 ring lugs and one of those two sizes would be a better fit on the bus bar and grounding stud in the trunk where I connected it than the M10 lugs. But in any case it's only 0.4 meters (about 15.75") long. That's pretty lame, they should also offer it in a 1 meter length which would give plenty of slack.

I had to order their accessory part # 56-304 extension cable which is 8.2 ft long. I suppose that will be OK as it will give me the option of connecting the CTEK by leaving the driver's side window open about an inch and running the cable through that way since the electrical outlet is on the garage wall right next to that door anyway. And I won't have to close the hatch on the cord which I don't think is the greatest idea.

 

Close.
The main battery still powers all the peripherals (lights, HVAC, Infotainment etc) as well as the starter motor, EXCEPT for the brief period when the SS system restarts the car after a stop when the starter motor needs the full quota of amps that only the main battery can supply. Then and only then does the smaller battery take over powering the peripherals (so the main battery has full amps available) and once the engine has started again the main battery takes over and the smaller battery goes back to sleep.