As far as I know there are 3 files you can edit,
1 is sh4/data/UPCDATA select the submarine you want to edit and change the hitpoints accordingly
2 is sh4/data/submarine select the sub your useing and edit the .ZON file to the required hitpoints
Make a note of all the files you edited (make back ups) then go to
My Documents/sh4/data/CFG/userplayer context
and edit the equipment upc file to whatever you you edited they have to be the same.
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