You can take the retractor out and carefully pry up the black plastic cover, and twist it tight again while holding it in place. Do it slow and be careful or the spring and cap will fly out and hit you, or completely unwind itself. I just finished rewebbing the belts on my 78 sedan. It really isn't "hard" to do, just annoying and tedious, kind of nerve wracking hoping that the spring doesn't fly out and take out your eye!

I got my webbing locally from a friend at a upholstery shop, but ssnake-oyl.com carries automotive seatbelt grade webbing as well, a bit expensive, however.

For stitching, I used nylon upholstery grade thread that I got from a local fabric store.

You will need a heavy duty, or a up to snuff older sewing machine, with a reverse stitch feature to sew the webbing together at the latch(s). I used my vintage Bernina 830 Record and it worked beautifully. I bouht my machine at a local thrift store for $94, which was a steal for this swiss made embroidering machine which has a more than powerful enough motor assembly to handle heavy duty and thick fabrics.

Yeah it would probably be cheaper to do it that way, I considered it but I'm a DIY extremist and very confident (maybe over confident?) in my work, so I went and did mine myself. No shops locally would touch them, as they don't dare do any work on retracting belts due to the fact that IF they were not to work correctly after the work, they don't get sued over any injury. I can understand, but if something goes wrong, I only have myself to blame. The retrators are not very complicated though, I cannot fully understand why they may think something may go wrong...