You're trying to solve the wrong problem. HDToolBox uses its own algoritm to decide sensible values for everything, as long as it all adds up to the same total number of bytes (more or less ;-) ) there's NO reason why you need 16 heads instead of 8 on a harddrive that only has 4 ACTUAL heads inside it anyway. Kapiche?
The problem you have is that your FFS and scsi.device doesn't support large disks. Make sure you've got the LATEST FFS on disk and inside the RDB, and make sure setpach is run in the startup-sequence. WITH the scsi.device patch.
