Pull the hard drive, stick it in a computer running WinMFS, see what mfsinfo has to say, if it reports that the drive boots from partitions 2, 3, and 4, use fixboot option 2, if it says it boots from 5, 6, and 7, use fixboot option 1.After my HD XL starting rebooting I ran Kickstart 54 and the drive passed. Then I ran KS57 and now the unit freezes instead of rebooting. I have tried to run KS58 three times but it doesn't take, the unit boots up normally instead of going to the GSOD.
That'll make it change which set of partitions from which it boots.
If it doesn't help, you can always change it back.