Seat Belt Not Retracting

[Tow Me]

I have a nice set of red or carmine 3 point retractable seat belts. They were pulled from a parts truck and I realized the lap part won't retract on the passenger side. I drilled out the rivets for the plastic cover and found the cap that says "don't remove" was missing. Apparently that warning is there for a reason cause I removed a cap off my old seat belts. I didnt know, but there is a metal coil in there and it went everywhere. Luckily I still have all my digits and eyes.

Has anyone replaced these? Or tried to recoil them? I spent 45 minutes trying to coil it up tight but its hard to hold.