I would be heading up on the Friday as well and would be willing to meet at the mentioned service center.
Composing a list would be a good idea. Also if anyone is interested, the Bimmerfest website says you can park as a group if you arrive at the same time. I don't know if people would rather stick with Ontario cars, park in random spots, or try and park with bimmers of the same year and model. But, if people are interested in parking together at the show, a list would be useful for that too.