Hot Rods Help ID Intake carb adapters spacers

Need help to ID these Carburetor adapters or spacers I've never seen them before has a 3 bolt carb base that goes to two staggered pads I have a pair any help would be appreciated

 

Dang things look like they're step-dancing together with the stagger!
The vertical arrangement suggests something like Corvair or Nash with an integral manifold thar gets its top milled off to allow more carb...?

 

Btt