I have two bikes with slightly different geometries (my main ride is a size 52 CAAD10). When fitting myself to a new bike I try to keep everything the same from my previous bike. My priority is the saddle-BB height and the saddle fore/aft position, next is the handlebar reach (the frame's "reach" measurement + stem length), and finally the handlebar height (combination of the frame's "stack" measurement + height of stem/spacers + stem angle).

Replicate everything on CAAD to the Kona first (saddle position, stem length - (swap them?) ) then try it out. The Kona's headtube angle is shallower than the CAAD's so the replacement stem might be longer than 100 mm.