Simultaneous Downgrade and Remove?

Hi:

To restore state in Mach, I check the original build snapshot which 
contains the package names and versions.  Then, I calculate if I need 
to run a downgrade.  I then run a command such as:

$ apt-get -c /var/lib/mach/states/fedora-2-i386-mint/apt.conf install -y 
--force-yes modutils=2.4.26-16 popt=1.9.1-0.3 libacl=2.2.7-5 
rpm-devel=4.3.1-0.3 info=4.6-3 rpm-build=4.3.1-0.3 net-tools=1.60-25 
krb5-libs=1.3.3-1 libattr=2.4.1-4 rpm=4.3.1-0.3 tzdata=2003d-2 
beecrypt=3.1.0-3 initscripts=7.53-1 make=3.80-3

However, there is a package currently installed that has a file conflict 
between it and one of the downgraded packages.  In my case, librpm4.3 
conflicts with rpm-4.3.1.

For manual purposes only, I was wondering if there was a way to issue an 
apt-get command such that it would both perform the Downgrade and a 
Removal of a package.  I know automating this would require a change to 
librpm4.3's packaging ... so, I'm just asking for a way to rig this 
thing back to a sane build state.

thanks,

-- 
-jeff