Just wanna let a you know that 99-00 civic si and ex m/c is the same.. i know i physically check out myself it's a 7/8 not a 15/16 so.. don't be fooled!! one more thing if you do a rear disc swap for you civic Ek or Eg you can use any 99-00 civic si 94-00 integra or 93-97 delsol v-tech but you should use a 99 si propvalve only, because all civic boosters are the same.
hope this helps..thanks..