Jan, there was an old article re building exotic Pantera headers. Seems some bucks-up owner (not Gary Hall!) decided to build the Ultimate Pantera back in the mid '70s. He hired a race car shop to 'suitably' modify his planned super-supercar. They found an ex-NASCAR 427 SOHC engine and shoehorned it into his Pantera, along with twin turbochargers for a targeted 1000 bhp- in the '70s! Turbos heat the exhausts significantly so they decided to make the needed headers of heat resistant Inconel. Ultimate car needs an ultimate exhaust, right?
Back then, Inconel was an exotic metal used mostly by NASA and in missles, fighter jets and long-range bomber engines, and commercially only as sheet (with restricted access to buy). Inconel is a very high nickel/chrome metal and at the time most nickel came from the Soviet Union and Rhodesia (now Zimbabwe)- neither country very friendly to the USA. But the crew did manage to purchase many thin sheets, cut and rolled them into tubes, seam-welded the edges and hot-sand-bent the resulting tubes to make up needed turbo exhausts. VERY steep learning curve for the crew in welding and forming- not much info on Inconel forming back 50 years.
But things progressed slowly until one day the shop was visited by two trim young men in dark suits and sunglasses, who ID-ed themselves as U.S. SECRET SERVICE AGENTS! "Sir, the Government wants to know what you're doing with all that Inconel...." They could hardly believe their eyes when shown the exhaust header production methods the shop had devised for a hot-rod. Likely their official report to spook-central in Washington would be very entertaining to read, if located and maybe declassified.
Sad ending- by the time the monster was ready to drive, several years of shop time and some $900,000 had reportedly been spent or at least billed. About the same time, the car owner had had serious money issues and went bankrupt so the finished car was now up for sale. The magazine article was not specific as to what actually happened to the first million-dollar Pantera and this all predated the Internet. I'll try to find that old article in my magazine piles or maybe other old-timers remember more details. But $5000 for an exhaust system seems almost reasonable compared to that saga.
Cheers- J DeRyke