I've converted few panzers into Befehlswagens by making them
tracked Scout Vehicles and
modifying their armament and ammo to fit the radios which I give a high 90's value. Yes you will get the armour rating to rise, however, like Andy said you run a much higher risk of getting your HQ blow'd up real good.
I have made it though campaigns, even with my Befehlswagen being hit and blown up, but, this was only because the crew survived, if they don't, like the man said the campaign ist tote. I've found another solution is to give them their own Halftrack,usually an FO Sdkfz 250/1. This way you can keep your CO closer to the action without being tempted to get your kills up.
This is usually my downfall when I jump into a BefehlsPanther or Tiger, I can't resist riding the thunder into battle and then having some JABO stick a 5 inch rocket in my butt
or some irrant PIAT Team toast my toes
.
Prosit!