Look you either do it right or you use a cursor to call that sp a couple 1000 times.

I garantee you that the cursor will be slow as hell.

Redoing it right might take you a day or 2 but that'll be the end of it.

With the cursor version, you'll be cursed with a slow system and complaints for the rest of your life.

Take your pick, but I know and told you what I'd do.