General question about timing

I'm helping a buddy time his boat. He was told he should have 38 degrees total timing.
If his cam was put in ahead at 3 degrees does that amount need to be considered when establishing the setting for the timing light?
I know any distributor advance also need to be considered i just dont recall if the cam position must also be considered.

I'm getting old, i used to know this answer and i think it needs to be included but it seems to easy to ask someone first.

Spark timing is referenced to the number one piston at Top Dead Center. If the cam tiiming has been altered, then the factory spec may not be too meaningful any longer in terms of optimum performance, but would be a good place to start.