Here's a toughy...

I installed an gm9-aux input onto a monsoon system from a 2001 Blazer. The problem is that several lights are burnt out in the Blazer head unit. I have a replacement circuit card (where the lights are soldered in) from another Blazer Monsoon Head Unit, but it's one that doesn't support gm9-aux. If I swap out the circuit board, will that negate the gm9-aux compatibility?

The only reason I ask is that it would be easier to swap the card than to re-solder the bulbs.