I have a lifetime subscription linked to a sony adapter that I would like to use in my 2008 Grand prix. The problem is the GM xm-ready OEM radio in the Grand Prix, which I want to use with my sirius subscription.

My question (I am sure this is not the first time a similar issue has come up): is there anyway to use the sony adapter with my GM oem radio (for examples, converters to modify compatibilities among different manufacturers' head units). The goal is to not buy another subscription, if I can avoid it.

What other issues (e.g., antenna) would I face, if I used the sony adapter, assuming it is possible?

Any help/thoughts would be much appreciated