How to wire after-market Satellite radio to power on even key is removed?

I enjoy listing to my after-market $77 annual subscription Sirius satellite radio and IMHO, it's a must for Taco drivers.

My Ext satellite radio has 90 mins memory function and I would like to use it.
It's pretty useful when you go to shopping etc and come back and you could skip the songs that you don't like.

Unfortunately, Taco 12v cigarette jack kills the power as soon as you remove the key from the ignition and I was unable to use above feature.

Does anyone know where to tap the 12v constant power and hardwire the 12v satellite radio's car power jack?

I don't feel like paying a few hundred dollars for factory satellite radio add on.
I appreciate you guys help.

 

Hot damn! that's awesome tutorial. Thanks for the hot link.