Carburetor for 1978 Chrysler New Yorker with 400 engine

I have a 1978 Chrysler with 400 engine with original Carter carburetor and lean burn system. Looks like I need to get the carburetor rebuilt. Should I rebuild or buy a new one? Would like to keep the lean burn on. Would the original work if I delete the lean burn later? Any new carburetor that would work with both lean burn delete or with lean burn?
Author: Fred A