Thanks for getting back to me.
The problem I have with just following that guide is that trying to sim with Ursoc at +6 gives me weird values like stamina not being worth anything. The post I'm referencing was something Yellowfive mentioned, where because the difficulty wasn't challenging enough for the gear, the sim wasn't going to be accurate (I'm very roughly paraphrasing, the explanation could totally be something else). Yellow then linked something (or maybe just talked about?) a way to use custom batches to see your chance of death at different gear levels, resimming at higher M+ levels if your chance of death was too low, and using that to help determine what M+ you should use for. Does any of that sound familiar?