Permanent Battery Tender Install
 

Didn't drive the miata much this summer because the AC stopped working. I had pulled the battery out to keep it charged, but I want to install the wires for the battery tender so I can plug it up in the car without having the wire pinched in the trunk lid.
Any existing holes in the trunk I can use? Or suggested areas to drill?

This is a NB btw. I searched and found threads where the NC crowd pulls connectors through the front grill. Also found one guy that installed a receptacle next to the license plate, it was ugly to say the least.

Hook up at fuse box in engine bay?

I have been thinking about wiring a bulkhead connector into the hole where my antenna was:
XRC? (Extra Rugged Circular) Sealed Plugs and Receptacles - Molex

For balance charging to work on my lifepo4 I would need 6 pins.

Fix ac, no charging issues, enjoy Miata more?

If I am interpreting correctly, he doesn't have charging issues, but wants the tender located in the car permanently. for easy winter storage.

That said I am very interested as well because I'm planning to do the same with a battery tender jr.

I'd suggest a C Tek battery charger. They claim they can be left on indefinitely and won't overcharge a battery. It's also compatible with AGM batteries and has a recondition mode.

This ^

It has been on and off the charger over the summer, but the tires just do not work when the temp drops. I wanted a more permanent solution for the winter. I might just pull the fuse for the trunk light and leave the trunk open. Probably safer that way with any fumes/heat.

Positive from Tender to ring terminal at the starter.
Negative to a good ground.

You could add a quick disconnect if you want it out of the way. I'd throw a fuse in for just-in-case