My mach 1 was ordered through DSO 95 and shipped to the Philippines. I did not know anyone there who had a gold glow '73 Mustang while I was there.
As to my reason for swapping out the Cleveland, I was racing at the time and my motor was highly modified. I found I had to turn to many RPMs against the big block Chevys to be competitive. A lot of the wealthy Filipino "playboys" were pulling the motors out of their Mustangs, Camaros and Firebirds and replacing them with small Japanese motors. There was a thing going on called the gas crisis.
Anyway, I was able to pick up this 428CJ motor loaded with a lot of "SK" parts for less than $100.00, along with a Toploader. Out came the Cleveland and C6 and in went the 428CJ and Toploader which I still have installed - - pending the installation of a 545 (460 stroked to 4.500" with a .030" overbore).
Incidentally, I still have a couple of Clevelands in the garage - - open and closed (Quench) chambered heads, just in case I ever want to go that route again.
When all is said and done, I am a modifier, not a restorer. So, I guess the response to your question as to "why" is because that is how I felt at the time.
As of this writing, that approach has not changed
.
BT