I remember the support on my B-bodies, but I really haven't messed with a-bodies enough to remember. I would imagine they have the same type of support so you don't warp the firewall. Especially with manual brakes.
I would go look at my Dart, but I can't get close to the front of it right now, did a final push to get moved this weekend and the back of the storage unit is packed full of 'stuff'. Time to reorganize...