well, the service manuals should provide disassembly instructions, the issue is that the mk4007gal has been discontinued, now, from what i´ver learned the MK series consists from MKXXYYgal, XX being the size in gigabytes (taking in to account gigabyte = 1,000,000,000 bytes) and YY being the generation with one detail, even numbers are 8mm while odd numbers are 5mm, the MK4007gal has been discontinued, the MK4008gal DOSNT FIT; 8mm high, the MK4009gal is the currently available 5mm drive, i found one for 93 euros + vat, the issue is getting one and fitting it,