[Chrysler300] Steering column 'rag joint' assistance on Hurst

Hello Group,

I seem to have some excess play in my steering, and in tracking it down it appears to be mostly from a mysterious (to me and my manual) "Double Coupling Assembly" as shown in Figure 1 on page 19-32 of the 1970 service manual.

My Hurst has the "Double Coupling Assembly" as opposed to the "Single Coupling" variety shown in Figure 2.

There is a fair amount of information on the Steering shaft coupling (smaller, squarish metal coupling device), but no mention anywhere about the other part of the Double Coupling Assembly, which is surrounded by a round, thin, metal can, which I presume is some sort of heat shield to protect a 'rag joint' (as we used to call them) from the heat of the exhaust manifold? What is under this can, what is it called, and can I get a new one? It is original on my car, which has only 71K miles on it, but is of course now some 47 years old and those exhaust manifolds have been putting out a lot of heat not too far away from this joint all that time. The play in the steering seems to come not from the metal coupling, but from whatever is under that tin, round heat shield.

Any help appreciated.