2005 Accord Project

Just started driving an 05 Accord and looking to add 3.5mm aux. Here's what I've gathered after poking around the web:

-There is an auxiliary port on the bottom of the radio that can be accessed by unscrewing some of the console.
-There are products sold on eBay and Amazon for $25 that have a white plug that fits the port under the radio, runs to a small box and then a 3.5mm cable comes out the other end. Most of the 1 star reviews say that the sound stopped coming out of the back speakers or one of the sides after a week or so.

Here are my questions:

-What kind of plug is the port on the radio? Does it have a name/is it Honda specific? Can I buy that plug anywhere?
-Does this port come before the preamp or do I need some kind of preamp?
-I'm guessing that the little box is just a conversion point for the wiring?

Ultimately I would love to build a simple solid piece that connects the aux port to a 3.5mm female so that I can plug a standard aux cord into it. Can't really tell if this project is over-ambitious for me. It also feels like this conversation peaked around 2011 and I don't know what parts are even available.

Any answers / insight / ideas would be greatly appreciated. I'm excited to resolve this. Thanks!