Total Blitzkrieg Wave
A total Blitzkrieg Wave is a wave of 3 Opel Blitzwagens, 3 Kubelwagens and 3 Zundapp KS750 motorcycles. It's one of theese blitzes where you would really want your AT guns placed. If they can't do the full job, however, you can always help them by calling artillery to thin out the numbers and heavily damage the others. Unless you haven't got many bunkers and pillboxes, calling Naval Artillery is also a good idea, though this can be somewhat a waste of TP and a big risk of losing your bunkers and troopers.
How do I kill it?
Call an arty and those annoying things will be gone for good. M3 AT Guns and AAA should do the honors too and/or mines at the top of the battlefield. Gunners, BARs and M3 Grease Guns can rather easily kill the crews from vehicles.
Using TNT is good for killing the Opel Blitzwagens and the Kubelwagens but not very effective for the Zundapp KS750 There's also a large risk of your engineer getting shot at so this method is impartial and ineffective most of the time.