We have. I can’t find it, but I overlayed the KFP building on Toon Lagoon and it just works. They’d have to turn one entrance 90 degrees (Kong side), but it fits.
Although, frankly, just converting Toon Lagoon to KFP could work too. Make Dudley a retelling of the first movie (Legend of the Dragon Warrior), make Blutos a Furious Five “training session,” Wimpy’s becomes Ping’s, and The Olive is replaced with Master Oogway’s Play Garden. Add a flat across from the amphitheater (the balloon spinner) and put a martial arts stunt show in the amphitheater itself.
Boom.