On mine, the holes through the aluminum were very rough, so I deburred them. On the other side where the bushings went, I glued them in place with thin CA (crazy glue).
Instead of the stringing tool, I stretched the last 3-4" of string to make it straight, then dribbled some of the same glue on the end. Made t stiff and easy to thread.
I did buy a kit, but all I used was the string.
The WIT instructions worked for me: http://www.lichtsinn.com/PDFs/Restringing-Day-Night-Blinds.pdf
Not sure if Spectra/spiderwire has the right texture for the blinds to operate properly. It's also fussy about the knots you use.
Norm