size of the object header

Hi,
 i hope you will excuse me for sending somany mails just over the past few
days. once i get the hang of it, should be okay
my changes to the collector requires the object header size to be 8
instead of 4 which is the current obj header size. one potential place
where i need to make changes was indicated by an Assert failure at
binder.cpp::CheckMscorlib() where pOffsets->expectedOffset is compared
with offset. how should i go about making the change to avoid assert
failure. i tried looking for MscorlibFieldOffsets but not able to
understand how its getting populated. Also if i need to make changes in
other critical places it would of immense help if you could mention them

thanks & regards
archana