Ive searched high and low for a throttle cable that is the correct length. Ive got a 1989 Regal on a JD Chassis with a Ford 460. I have checked the JD parts manual and come up with a part number of RE38473 but when I look for that part using the number I dont get any results and my local auto shop are no help. Any info would be appreciated.

You may have to repair the old one. OEM replacements may not be available. Some shops may be able to splice the old one, or there may universal kits online. I was able to find a kit for the GM 454 version a few years back.

Let us know what you find, good luck.