Hello Geoff,
Sorry to hear you had a problem with your car... which is also at the same time all your Chevy buddies will just happen to drive by and give you words of encouragement!
I hate to say things like "That has never happened to me" cause you do know what will happen next. I don't know how my pewter Mach 1 (Money Pitt #1) ever survived me. I was involved in a lot of very illegal late-night drag racing at one time. Since I ran against some big-block cars, I had the pedal more than firmly mashed to the floor. Besides the indentation of the pedal in the vinyl insert part of the carpet, I broke the black plastic part of the pedal twice, but never the cable.
The original OE throttle cable is D1ZZ-9A758-D @ 22.50". It was replaced by D1ZZ-9A758-H @ 22.50". Both of these are eyelet and clip style. Although the part number never changed, there was a running change on the accelerator pedal assembly where some over-travel brackets were added. Money Pitt #1 is a late build car (7-28-71) that has the brackets on the accelerator pedal, so evidently, that modification was the fix for overstressing the cable.
An additional change took place in late '72 production (6-19-72) where the '73 style accelerator pedal and cable were now OE. The D3ZZ-9A758-C cable is 23.25" and attached to the accelerator with a snap-in grommet. A much easier solution for those of us that are not quite as limber and with perfect eyesight as we processed...... a "few" years ago!
I have a couple of sources you can check since the repo cables don't seem reliable. I have used them before but can't guarantee reasonable prices. Both of these vendors specialize in NOS parts obtained from Ford and Ford Lincoln/Mercury dealers, so they understand the value of NOS versus repo parts. Green Sales shows one and NOS Parts shows two. Not sure how often their inventory is updated but that is what is shown today.
https://nospartsltd.com/product/d1zz9a758h/
http://www.greensalescompany.com/
If you haven't already found a cable you could contact these two sources to check the availability. If these don't pan out let me know. I have one other source that shows D1ZZ-D and H but can be a PIA to deal with and I only use as a last resort!
The red arrows point to the brackets on the "new and improved" D1ZZ-9725-A
Second picture illustrates the grommet hole on the D3ZZ-9725-A
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