Truvativ isoflow crank removal.

Hi, I'm looking at / replacing my crank arm/s after the right hand side pedal has sheared off and damaged the thread in the arm. Could anyone please advise of how I'd do that. I've taken the outer cap off and am presented with what looks like an outer threaded area where a crank puller would screw into. Centre being an 8mm nut. Just need to know if I'm on the right path. Got an 8mm Allen key which fits into the centre. Seen a few different crank pullers of differing types and from looking on here some that don't need a puller. Will post a picwhen I've worked out how to 🤔 cheers in advance guys n gals