I was there 1967 - 1975 ('71/'72) and had never heard this story.
Only 2 of these "Lawman" Super BOSS 429 Mustangs were ever made by Ford for tours to U.S. troops in Vietnam, Japan, Guam, Hawaii, & Mainland military bases. It's the only Ford Made BOSS 429 Mustang that's automatic in the world,1,200hp, runs a quarter mile in 8.4 seconds at 185mph.
Top speed depends on how it's geared, but it's well over 185mph.
For the Vietnam tour the cars were shipped through a private shipping agent. I flew later but was 3 days there before the cars arrived. General Barrow was excited and looking forward to see the SUPER BOSS, because he wanted to make a trial run. But his main idea of course was to do something good to his guys. While we were having dinner, I got a telegram that a container with "application forms for wrecking" was fallen on one of the Mustangs. I was really upset - it was not clear at that time, on which Mustang the container had fallen. Later my thoughts were confirmed that it was the SUPER BOSS.
I pulled the general over and informed him about the bad news, but he took it like a true Marine. He offered me a military airplane to get the second SUPER BOSS over and no, he would not accept any 'NO,SIR'. When I told him, it would take another 5 weeks to finish the second SUPER BOSS, he shook his head and said: 'You have 72 hours to bring it here. Get your stuff and we'll gonna make it".
Well, I flew back and within short time we gathered everything that was needed. A military cargo airplane picked us up and back we were. A general - especially if he got the SILVER STAR in the Korea war - never accepts an 'impossible'. A true Marine makes it possible. My lesson back then.