I guessed and found the new site,
www.nhra.tv
However it looks like the ability to subscribe is turned off and I was not able to sign in.
This is from the "About NHRA.TV" page:
NHRA.TV
Reliable & Exclusive drag racing content on-demand
Stream all 24 NHRA Mello Yello Drag Racing Series events. Plus, watch 2017 and 2018 race video on demand as well as historical race footage, exclusive exhibition matches and coverage of the Sportsman and Pro Mod TV broadcasts. Live video will be available on Fri-Sun of all races, with audio available on almost all other race days.
NHRA TV brings you:
Improved reliability
Faster availability of video-on-demand content after an event concludes
Easier to select content on demand
Watch wherever you go on multiple platforms - iOS, Android, Roku and Mobile Web
Catch up on episodes of your favorite NHRA TV shows
Refined search functionality
Improved customer support
Ever-expanding library of archived content
Time will tell,
Biil