Interesting article.
Found a few misleading statements.
"The Mach 1-style tape stripes were a $23 option you could put on any pony car..." INCORRECT
For 1973 this is incorrect. The only two body types that one could order the previous years' Boss type tape stripes were the coupe or the convertible. And they HAD to have the Décor Group ordered first to even allow these stripes to be ordered.
"so almost nothing changed between mid-1972 and '73: Color-keyed polyurethane bumpers (rebounding on rubber blocks in front, crushable and fixed in the rear) became standard" INCORRECT
The front bumper was the only Color-keyed polyurethane bumper for so-equipped 1971-73's, with the 73's being a little larger to incorporate the bumper's mandatory 5 mph crash standard. All 1973 Mustangs were equipped with this polyurethane bumper. The rear bumpers on 71-3's were never color-keyed polyurethane.
"The '72 351Cs had already switched to a lower-compression open head, and for '73 they managed to hold the line at 266hp" INCORRECT
Later in this SAME article, "But by 1973, the Q-code Cleveland boasted the highest horsepower rating of any engine in Ford's passenger car lineup: Company sales literature shows 246hp and 314-lbs.ft. in Mustang/Cougar". This is what I have always understood to be correct for the 73 4-V Cleveland. I have heard the HP ratings were recorded different for 72 and later in that they used HP at the rear wheels vs. at the flywheel for 1971 and earlier.
"For 1972, the Boss {351 HO} switched to the open head with 9.02:1 compression and plummeted to 277hp. As there was no '72 Boss Mustang, it was a seldom-ordered option known simply as the H.O., and is extremely rare, in the 400-500 produced range."
The correct number seems to be 398 units. They were all 4 speeds and could be ordered in any body type. 366 were Mach 1's. Rare cars!!!!
Just trying to keep the info correct as much as possible. I am still learning. This info is correct as to what I have learned and understand. If anyone has any info contrary - please post up and for those who care - we can try and figure it out...
Ray