Exclusive DetailsHeidi and Spencer Pratt are finally splitting up ... briefly, anyway ... because they are taking part in "Celebrity Wife Swap" and taking home a nice check for it too.
According to our sources, the O.G. most hated couple of reality TV shot an episode that airs next week -- and they'll be swapping with seven-time Olympic medalist Amanda Beard and her husband.
Our sources say the Pratts took home $50,000 for the gig ... which we know is nearly $20,000 more than some other celeb couples have been paid.
Good for them ... but let's hope Amanda got twice that amount.