I tried these steps and was successful, but with concern.  I read the link
you mentioned, but for modifying an assembly step 1 is not successful for me
at all.  TlbImp fails to create a PIA for my assembly because I can't make or
get my hands on a PIA for MSXML.  MS told us not to sign it.  I can't change
my TLibs, so we were directed to modify the non signed interop to remove teh
MSXML dependency and then regen the type lib.  The problem is that I am not
starting from managed code, and the PIA attribute is not there.  

I added the PIA attr. to the IL, but I was guessing at some of the fields
based on other PIAs.  The IL looks like this that I added:

 .custom instance void
[mscorlib]System.Runtime.InteropServices.PrimaryInteropAssemblyAttribute::.ctor(int32,
                                                                           
                          int32) = ( 01 00 03 00 00 00 09 00 00 00 00 00 )

I was a little nervous to fill in the binary data for this Attribute.  The
Constructor shows Int32, Int32, but there are 12 bytes of data, not 8.  I can
tell which are the major and minor version (3.9 in this tlib's case), but I
don't know why the first value is  01 00 and the last it 00 00.  Not sure
what these values are setting, but they are in other PIAs and appear to work.


What do the first short and the last short of data refer to?  Is it OK to
hand enter this data in IL?  It worked now, but will it always?