Cam chain tensioner replacement

I have a 2006 rocket that had some transmission work done about a year ago. The only problem with the repair is that they didn’t entirely reinstall my cam chain tensioner. (I’ll leave a picture below). Forgive me if my terminology is off, but they left out the rod with the head that goes through the center of the assembly. So in other words there’s just a hole in the side of my motor. Due to starting a new job in Texas, I haven’t been home very much since it was repaired and therefore I haven’t ridden the bike basically at all. I might’ve put 50 miles or so on it since. And along with that I just didn’t really worry about this issue because it wasn’t being ridden.

Now for the actual question. I need my bike 100% within the week because I’m riding it out to Houston very soon. I already have a new tensioner, but no shops can do the installation before I need to leave. Is it worth it to do it myself? And how would I go about doing it?

Thank you!!