HaloMods "Classic" Read-only Archive

I'm following pokecancer's pmi tutorial, and pretty much everything makes sense to me except how to find the indices and vertices sections in the model meta. in the tutorial he just tells you where to go, so I can do it in those circumstances but when I want to do my own model injections in the future I won't be able to find them. I tried using the offset lists from sparkedit, but I couldn't figure out what to follow.
I just need to understand the layout of the indice/indice/vertice sections.

thanks
Budro