2018 Factory Sirius Antenna

I have a 2018 Tacoma SR. When I bought the truck it had a factory Sirius Antenna on it. Does anyone know where the antenna terminates. I'd like to install an after market Sirius radio, while using the factory antenna. Any pointers on how one can do that?

 

Back of OEM radio head and shark fin on roof. Your problem may be the lead behind the head may not match the lead for the aftermarket one.

 

Call Crutchfield and see if the have an adapter. They had one for my 18 Civic and I was able to install an Alpine head unit and use the OEM XM antenna.

 

Good call. Totally forgot about them.

 

You don't have Sirius/XM with your OEM head unit?

 

Thank you all for the replies. I'll have to look at the back of the unit to see which wire is the one for the Sirius antenna. I've taken the radio out of the dash, but the wires have very little slack, and its tuff to see which of the wires is the correct one. I found the following link for an adapter that looks like it will work, I just need to figure out which wire
https://www.youtube.com/watch?v=xw8YkG6EDH0

@mmatheny: No my truck did not come with Sirius/XM, but it did come with a shark fin Antenna on top.