missing intonation screw

recently bought a used Reverend 5 string - just changed the strings on it and discovered that the low B saddle is missing the intonation screw; spring is still in place, but the screw is gone. Reverend was kind enough to send me a replacement screw and spring. my question is - can i just screw the new intonation screw into the existing spring, or do i need to replace both spring and screw? any guidance would be greatly appreciated. TIA!