8 am is perfectly legal but may be a little early for some neighbors. I don't think it'll kill you to start at 9? There has to be prep work and clean up you can do before 9. I always try to do my best to please the neighbors. That way you can ask them for a favor in the future. You won't hear me doing much before 9 on weekends. If I get up early, it is to go hunting or exercising, which I do away from home.
Always remember that the poor schmuck may have been sent by his wife ... I would have asked when he would be happier with the noise and tell him he can come by next weekend at that time with some fresh Starbucks drinks to watch.
Georg