Retro Rush

Does anyone know the first year Pulp Hero was published? I ask because I vaguely remember it before I took a long sabbatical from table top rpgs.

I know that Pulp Hero is the current resource book for the Hero System but was there ever a time that both Justice Inc. and Pulp Hero overlaped, or did Pulp start getting distributed only after Pulp Hero was discontinued?

And what were the differences between the two, originally? Did one contain the core rules while the other was simply a resource book?

And does the current Pulp Hero resource book pretty much have everything that was in Justice Inc.? In other words, if I bought Pulp 5e, would there be any reason to track down an edition of Justice Inc. other than  it's a hard copy?

Thank you.

Cthulhu, Gamma World, Magnum PI, Miami Vice, and a source book for Ancient Rome.