I don't have a Vortec ignition system, but I did a little research. I typically use Standard parts for electrical replacement as they seem to be of good to high quality and last a long time.
I looked on their site for the dizzy cap -
https://www.standardbrand.com/en/ecatalog - and found it, along with some instructions for under the hood. Hopefully these will help.
https://eaccess.smpcorp.com/eCatalog...MD/GF9813B.pdf