While trooping as a Stormtrooper last year I began to research building an “A New Hope” Darth Vader. I am prod to say that I finished my Darth Vader costume and have been approved!
So while the site is still called TK41973 I am also SL41973 (SL =Sith Lord). When you get a new costume approved your ID number doesn’t change. That number is yours for life. The two letter prefix is added to your 501st membership. Since I have two costumes my 501st designation is either SL41973 or TK41973.