Need to start a virtual machine but missing nic is preventing this:

I have need to recover some data from a guest on host which has been shutddown for some time. The host had one of it nic removed at some point. It is not likely to be replaced either.

When I try to start the guest in question I get this:

error: Failed to start domain inet09.harte-lyne.ca error: Cannot get interface MTU on 'br1': No such device

I tried editing (virsh edit guest) to remove the interface:

<interface type='bridge'> <mac address='52:54:00:35:a2:8a'/> <source bridge='br1'/> <model type='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x08' function='0x0'/> </interface>

I saved the changes and tried to start the guest. but I got the same error. Then edited the guest config to say:

<interface type='network'> <mac address='52:54:00:35:a2:8a'/> <source network='default'/> <model type='virtio'/> </interface>

How do I configure this guest so it will start without the missing nic?