The Carter 832s was originally used on a 134 CID 4 cylinder Willys.
AS A GENERAL RULE FOR BEST RESULTS!!!!!
When migrating an OE (original equipment) carburetor from on engine to another, the donor engine should be within 3 percent displacement as the donee engine. 3 percent of 134 is 4; thus this carburetor might be a good choice for FOUR CYLINDER engines from 130 to 138 CID.
The 3 percent will be increased for A/M (aftermarket), perhaps to as much as 10 percent. This because A/M carburetors are calibrated much richer than OE carburetors.
Somewhere, there is a Willys guy that would love to have this carb. Or, you might get a 3x1 manifold, buy 2 more of the 832s units, and put 3 of them on your 261.
Jon.