Coolio was set to headline the first Before Death Residency Show in Vegas

Coolio before his sudden death last week, he was working on a lot — including the fact that he was set to headline his first-ever Vegas residency this month … TMZ has learned.

Shortly before his death, Coolio was in talks with a production company called Fan Rebellion, which is producing a Vegas residency show called Boombox!, held at the Westgate Las Vegas Resort & Casino … which, according to FB’s chief creative officer, Jimmy Maines.

Boombox! tends to specialize in old-school hip-hop artists from the 80s and 90s – and has booked big names like CeeLo Green, tone loc, and others – so it’s right up Coolio’s alley .. and that’s why Mines and co. were negotiating to bring him on stage.

Maines tells us the plan was for Coolio to come in and headline the show starting in late October and running through the second week of November … for a total of 10 days, with one show a day 5 days a week. In short, ten concerts.

We’re told Coolio would be one of the few MCs – he’d be headlining – and Mines says he’d only do 3 songs if he wasn’t asleep. Tracks considered… “Gangsta’s Paradise”, “1, 2, 3, 4” and “CU When U Get There”.

As for the specifics of what Coolio had in mind…it’s pretty interesting. Maines tells us that Coolio made several stage requests for his scene — including lots of props, more than 10 dancers, a 2-story backdrop screen for visual effects, and two or three outfit changes.

We’re told Coolio wanted his headliner to be a look back at his story, and he’s excited for the next chapter in his career.

Of course, his death brought things to a sudden halt – Maines told us they’re now taking that window down at the end of October and hope to pick it up in December with a whole new line-up. Indeed, Coolio, dying, threw them for a loop.