To Tony's comment about measuring the effort to turn the steering wheel. Yes, there is a contraption that is affixed to the steering wheel, with springs, to measure the force needed to turn the wheel. Might even be shown in the FSM? Or some YouTube videos or Chrysler MasterTech videos.
From what I remember seeing, the "heat shield" is really "gravel shield" that was federally-mandated as some vehicles had had issues steering the vehicle when gravel would get lodged in the lower part of the column. Whatever it really is called is in the FSM in the area of "changing spark plugs", as they indicate to remove it to change #7 plug. Then re-install it when done.
On our '66 Newport 383 2bbl, I did the removal to change #7, then put it back on, like the FSM indicated. After that, I just left it off with NO issues in longevity or similar. BUT, the car is used normally and not raced or any other HD service use, so exhaust manifold radiation is NOT an issue. On the other hand, there is plenty enough of free air space under the hood of a '65-'66 C-body (pre-collapsible steering column years) to cool things down, it seems to me. Always made sure to have a good fan clutch in the mix, too. Just my experiences, FWIW.
Happy Holidays!
CBODY67