The board arrived, looked good and was suitable for purpose... however, it ended up with two problems... still better than the dead one but annoying.
1) the headphone port on the replacement board was "bad" meaning that it always believed that there was a headphone plugged in so it would not play any audio through the speakers. the audio did work in headphones. the headphone port is a bad design in my opinion. My solution: Desolder the headphone jack and replace it with the one from the old motherboard. This requires a good rework tool set (hot air, surface mount) and some luck (I told my wife it was skill).
2) Turns out that many old MBP systems have a Power on problem that appears to be unfixable. plugged in and powered on works... but... don't power it off on battery. the power button will not restart the machine. so plug it in and get it going. Sleep works well and recovery from sleep works well.
The price is right and otherwise the machine would not have been recoverable at all. So, it was a good deal. Testing all of these things on a recovered logic board is probably not practical...
Re-Use.. keep the pressure on for Right to Repair.