We've now developed an official drivers.txt file for IROC. Here's the download link to it: http://nascarheatracingleague.com/downl ... rivers.txt.
You might need to do a right-click and "Save Link As..." to download it as a file. Also, the link is to the website; it's not a forum upload. So, we'll post a follow-up note whenever we edit the file. It includes everyone who is currently signed up for the series. It also has the #00 NHRL IROC car.