Interchangability of parts acros model years Birel

I am currently in the proces of buying a new to me Birel 2014 kz for cheap. The chasis is a litle scraped, so my question is if a 2013 Kubica frame or 2020 Birel ( joust the steel ) will fit as in drop in replacement. Will I need to replace the sterring knuckels as well if i decide to “upgrade”?