Hello. I have an 84 Santana Ligero (closest LR would be a Defender... but engine more common in a Series) with a 2.25L diesel 5 mb engine. It developed a loud knock after a particularly heavy hill climb (east TN, USA). I nursed it home and pulled the head. The #4 cylinder had the hotspot within the cyclinder and indentations on the block where the hotspot had been beaten into the block. I ordered a new hotspot and pin but the new hotspot simply drops in without any effort or retention capability. I think the old hotspot was simply rocked back and forth within the cavity thus causing it to be enlarged and creating the indentation within the block (see photo). Since the head won’t retain the new hotspot AND the block has on indentation right under where the hotspot would be, I assume both are toast at this point. My questions are: Are there any options for fixing the head to retain the new hotspot and can the block be repaired that anyone knows of? I have a 78 3 mb 2.25L diesel so can swap but would like to find a solution to keep the 5 mb engine. Down the road I may do an engine upgrade to a 200Tdi or GM 151. Appreciate any assistance.