m110 engine

HELLO ALL, I HAVE JUST BOUGHT A 280E FROM EBAY WITH A BLOWN ENGINE AND AM LOOKING FOR A GOOD UNIT TO REPLACE IT WITH. ANY GENERAL HELP AND ADVICE WITH MY FIRST W123 WOULD BE VERY WELCOME, HAVEN'T COLLECTED IT YET! THE SELLER MENTIONED THE AIR CON DOES NOT WORK, IS THERE A COMMON FAULT WITH...