I have a 2003 Deville base and I am going to be replacing the head unit.

I know I need a GMOS-06 adapter to keep the onstar and data bus happy. I did some searching around on this forum and found that the gmos 06 can cut out once and while? The posts were all from a year or more ago....is this still the case? Does the gmos-06 have problems still? Is there a particular model?

Just haven't seen anyone post recently about it...

Also, is it basically plug and play? Will I need to run any constant power wires anywhere?

Thanks.

It is plug and play, no running wires, although you may have a little problem fitting the module behind the radio. I extended all my wires and installed the module under the drivers knee bolster, which made it a lot easier.

As far as the problems with the GMOS-06, I can tell you first hand that I've seen about a 30-40% failure rate with the Metra Axxess pieces. A very few doa, but more often some form of audio/onstar problems. I've been using the PAC modules here at work and they seem to be MUCH better, I can't think of any problems I've had from them. Nothing's 100% perfect, but these are as close as I've seen. The one for your car would be PAC part # OS2-GM32 should you decide to go that direction.

Just man up and relocate the stock headunit. It will take longer to get it done but once you complete that there is no issues.