Guys am i reading this right? If this combo comes out legal you get BOTH mangler attack and second primary attack?

Its not IF, it IS legal and has already been used in major events placing in the top 4. If this was a significant divergence from the rules ffg would have stepped in by now.

On the same note I expect this to be FAQ'd.

It's totally fine. It's an expensive combo that is just a back door to an extra attack, which we have many ships that can already make. It just doesn't explicitly say it on a title or Pilot, but that's not a problem. The new timing chart must be followed, which allows this explicitly and removes any meaning of the word immediately during the after attack step. It's a solid but not great exploitation of upgrades. Gives your a reason to keep playing your IGs, which have all but disappeared from the meta. That's a good thing.

You have two triggers, one has the clause "immediately", and you can choose to ignore that bit of rule, because of simultanious triggers, seems like a bit of rule exploration to me.

This does seem a bit grey. So gunner says 'immediately'' how are we defining this. If you attack with IGB's ability before using this would it still be immediate? And I don't think a letter on the internet is sufficient enough proof. Another FAQ please.

From Frank:

" “Immediately” doesn’t really have a meaning. It is old verbiage that is trying to help players understand that it happens “now” verses three rounds from now. It is an eleven letter monstrosity whose only effect is to clutter up what little text space that exists on Upgrade cards. It has no effect on priority or timing and we have avoided using the word on more modern cards due to this. Don’t worry about it.

Frank Brooks"