Cub Cadet engine swap update.
Removed the Briggs Intek twin and set the Kohler 20hp in place with couple bolts and Immediately noticed that the Kohler exhaust system was not going to fit. The Kohler came off a Craftsman tractor. Everything else bolted up ok electrically and mechanically using the engine pulley and electric clutch from the Briggs Intek.
The Kohler engine uses a exhaust assembly when used on a cub (all welded together)
CUB CADET 751P10528E Exhaust Muffler when used on this Cub tractor.
I can eventually custom make exhaust system with torch and welder BUT weather right now is in triple digits in the shade or maybe eventually check with a local mower salvage.
Anyway good to know that the nice running Kohler 20hp can be a go as a engine swap on the CC with proper exhaust. (before I sold the engine and found out such later)