I'm the competition director/ tech director for the must see racing xtreme sprint series and I've already talked to Jim Hanks about this. We have decided that 360's with an aluminum block do get a 100 pound weight break.
Cool! I don't personally know anybody with an aluminum 360 (everybody I know is running ASCS/USCS rules) hopefully if there are any out there, this will give them an incentive to come and run!