ok i'm back with bad news, it doesn't work ...
the script is deleting the bad block so the output file is 135036 Kb
was before 135168 Kb
here is what I'm doing manually with an hex editor:
$5FA6000 is beginning of bad block
$5FC6FFF is end of bad block
$5FC7000 is beginning of next block
$83FFFFF is the last byte of the last block
copy data from $5FC7000 <--> $83FFFFF to $5FA6000
it means that block 1023 is the same as block 1022
am i right or wrong ?
My question now is does the dump have some kind of ECC or checksum ?