I believe the set seen at Carlisle is from the same collection. JR unloaded a lot of stuff at the Pate Swap in April and a couple guys from TX bought some and brought it to PA.
C2 long cast headers were on my 62 G Code XL when I bought it in 1987. Car was Dallas built in May (when the XL's first launched) and pretty original. I always wondered if they could have been factory installed maybe as a production trial.