Sorry, I saw one group and assumed that was it. I did not know about the PDX at the ARRC but I tell you, next year I just may rent a street car and get John Williams to show me how he does it.
I should note, here, that the Atlanta Region PDXes during quiet time were initially implemented to reward race volunteers, who, with 2 days of service, received reduced-price entry fees for the PDX ($20 for 2-20-minute sessions.) The kicker is that race drivers on site for the weekend volunteer to work corners and instruct. It's a great way to give folks on both sides of the ARMCO a taste of how the other half lives. It can be an eye-opener for both groups.
If workers don't fill out the field, slots are available for others for $100.
I've done 2 of these, and it's a heckuva lot better worker goodie than an event t-shirt or a one-use rain poncho! Thanks, drivers!