Here is the finished installation. It isn't a big deal but should make it more comfortable for those like me with thick toed boots and shifting. I didn't take a before picture unfortunately but it does extend the shift pedal almost 50%. The inside diameter of the extension didn't allow for a simple slide on over the rubber boot but I don't have to bother with the set screws that were included with the extension. It is larger than the pedal metal pin however. It can be easily be configured back to stock. To fit it on I pulled the rubber toe shift boot just a bit off the peg, sprayed it with silicon, stuffed the edge into the extension, and the extension did press on easily enough. It is very snug. I don't know how long the rubber rings around the extension will last or slide off. I may just keep a center one in place to keep the boot from being marked by the split metal of the ext. The extension does rotate well enough should shifting require it.
https://imgur.com/a/fIlrgQI