Seat belt retractor disassembly??

[72c20customcamper]

I purchase a set of reconditioned belts that the cover was cracked . I knew it going in seller was very open about the cracked piece . The belts in my truck the covers are perfect just need to re dye one to make a perfect set . Some of the webbing on mine has damage so I tried to take the retractor apart . I got it to the point that the nut is off the spring has released tension but the screw only comes out about a 1/2 inch won’t go any further.