I just reread your post - "hood pieces" - you aren't running sides with that exhaust, but no top either?

If no hood at all, then just make sure the shell is leaning forward at the same angle as the cowl - ( don't lay a '32 shell back, or stand it perfectly straight up and down on a car with a considerable forward rake..haha). Then just lay a length of wood or something from the center of the cowl to the center of the top of the shell. make sure it runs down hill, parallel to the belt line of the car preferably.

I have that exhaust on my Tudor - I have nearly burned myself several times - melted a couple sleeves on nylon jackets....haha. Man they look bitchin though.