Rattling heat shield

[dardal@xxxxxxxxxxxxxxx]

Hi all.

My 68 Lebaron is motivated by a 69 440 from a New Yorker.  This engine has the 
69+ air cleaner along with the left manifold heat shield (that supposedly feeds 
hot air when the engine is cold).  Well, at low rpm when hot, the shield is 
rattling (over 1500 rpm or so, the frequency is too high and the rattling 
stops).  I replaced one of the bolts that was missing (connecting the upper and 
lower part) and the intensity of the rattle and/or the rpm that it occurs 
slightly changed.  The part is not securely attached on the head.  All you 69+ 
owners, can you tell me how to secure that part and/or keep it from rattling?

Thanks

D^2