I've done it on an previous coach. I bought the kits at Camping World. The wider shades with 4 strings are more complicated. But you can google and find color coded diagrams that show how the cords cross over one another.
2015 Chateau 31W
2014 Honda CRV EXL w/ Nav
Blue Ox Aladdin tow bar
I ended up buying both the 300 yard spool and the re-string kit. I only used the re-string kit so far. My shades do not have replaceable grommets so the kit was not really needed. I followed the instructions on the video and it worked perfectly! The shade works like new. Now I realize that some of the other shades (that I thought worked much better than the one I fixed) need to be re-strung also.