The blonde rocker and the country crooner are planning to make it official at the Church of the Good Shepherd in Beverly Hills on May 5, RadarOnline.com has learned, but even that decision has been quite a battle.
"They can hardly agree on anything!" a source told RadarOnline.com. "Gwen wants to go big on this — and Blake wanted to make it an informal affair down home in Tennessee or their new place in Oklahoma — but he's not willing to go to the mat against her."
Going BIG will mean hundreds of guests — though even that number sparked a showdown for the No Doubt frontwoman, 47, and the cocky Voice coach, 40.
"Gwen's guest list was 700 people alone," the source claimed. "She also wanted to have a bunch of celebrity music stars perform — but he didn't want to turn the wedding into Woodstock."
They have agreed to perform themselves, according to spies, who revealed the pair will belt out Jon Bon Jovi's "Blaze of Glory" as a wedding song.
Meanwhile, the guest list has been whittled down to 400, and includes Jennifer Aniston, Justin Theroux, Courteney Cox and fiancé Johnny McDaid, plus Katy Perry on Stefani's side. Shelton's inviting Keith Urban and Nicole Kidman, along with country cousins Luke Bryan and Brett Eldredge — who insiders said will be his best man!
Plus, "they're seriously considering inviting Gwen's cheating ex, Gavin Rossdale, and Blake's former wife, Miranda Lambert," the source claimed, adding, "They're making sure to invite them with a plus one. Won't THAT be interesting?"
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While Lambert could show up with Anderson East on her arm if she chooses, Stefani's still running the show where Rossdale is concerned, the wedding insider assured RadarOnline.com.
And one more surprise: "Gwen knows Blake's out of his depth here with all this glam, so she's agreed to foot the bill for the wedding while he will pick up the tab for the honeymoon!"
But speaking of money, they HAVE agreed to sign a pre-nuptial agreement, sources told RadarOnline.com.
"They'd be crazy not to," pointed out one source. "Gwen's worth about $100 million, and that's about $60 million more than Blake."
Do you think Blake and Gwen will make it down the aisle? Let us know in the comments!
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