this is how data is organised on the various platformbuilder discs:
arm-arm720        fileset2
	DISK2 : 4992

arm-sa1100        fileset2
	DISK2 : 1447
	DISK3 : 3545

mips-r3000        fileset2
	DISK3 : 2790
	DISK4 : 2202

mips-r4100        fileset2
	DISK4 : 3578
	DISK5 : 1414

mips-r4300        fileset2
	DISK5 : 4992

mips-r4111        fileset2
	DISK5 : 1642
	DISK6 : 3350

ppc-ppc821            fileset1
	DISK6 : 2842
	DISK7 : 2146

ppc-ppc403            fileset1
	DISK7 : 4633
	DISK8 : 355

shx-sh3            fileset3
	DISK8 : 4998

shx-sh4            fileset3
	DISK8 : 1750
	DISK9 : 3248

thumb-arm720        fileset2
	DISK9 : 2790
	DISK10 : 2202

x86-i486            fileset1
	DISK10 : 4938
	DISK11 : 50

diff fileset3 and fileset2:
these are not in fileset2:
    /PUBLIC/COMMON/OAK/LIB/../CE/DEBUG/CCRTCPU2.LIB
    /PUBLIC/COMMON/OAK/LIB/../CE/DEBUG/CCRTFPW2.LIB
    /PUBLIC/COMMON/OAK/LIB/../CE/DEBUG/CCRTFPW2.PDB
    /PUBLIC/COMMON/OAK/LIB/../CE/RETAIL/CCRTCPU2.LIB
    /PUBLIC/COMMON/OAK/LIB/../CE/RETAIL/CCRTFPW2.LIB
    /PUBLIC/COMMON/OAK/LIB/../CE/RETAIL/CCRTFPW2.PDB

diff fileset2 and fileset1:
these are not in fileset1:
    /PUBLIC/COMMON/OAK/LIB/../CE/DEBUG/CCRTCPU1.PDB
    /PUBLIC/COMMON/OAK/LIB/../CE/DEBUG/CCRTHELP.PDB
    /PUBLIC/COMMON/OAK/LIB/../CE/RETAIL/CCRTCPU1.PDB
    /PUBLIC/COMMON/OAK/LIB/../CE/RETAIL/CCRTHELP.PDB