Franzcisic?
Franciszek
Kunc
Kunc is a surname of German origin (Kunz) - it may have had polonized spelling (there were a couple of waves of German settlement in southern Poland in ages past and it resulted in many surnames of that kind) or it may have original German spelling
the best advice I can give you is to look for people who do such research professionally - they know which doors to knock at
also there must be Polish emigree authorities archives in the UK - contact the Polonia institutions