"Does the crossover heat tube need to be blocked off if it is not rotted? Mine was a stainless replacement that I pounded in years ago."
No. As long as the tube itself is intact, there will be no exhaust leak (if the manifold crossover tube openings have not been wallowed).
Now here is the problem. If one defeats the heat riser valve, there will be very little hot air (exhaust crossover) under the intake manifold carb plenum to atomize the fuel charge properly and also the hot air choke draws the heated air from that source (via the crossover tube). The choke may not release fully or be slow in doing so. The heat riser does more than just provide hot air to the choke.
All of this also depends on where you live and what weather conditions you experience. While the ambient temp may not get very low, the humidity may be high and possibly lead to icing.
FORD installed this system(s) on most cars so it would be drive-able under most any condition.
Choke settings were usually adjusted for winter and summer operation. The heat riser valve itself was also lubricated with a special lubricant to keep it from hanging.
What gets me is the RS inlet pipe hanging low. Did the vendor offer a choice of pipes, one with the valve and one with the valve removed?
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