On my 57, the old cable was broken, When I replaced it, I filled it from the speedo end, with wd40. It has always worked correct and steady. Even when changing the 2-speed rear, it works smooth.
57 GMC LCF 370 55 John Deere 40-W 59 John Deere 430-W 2000 GMC 4x4 56 John Deere 420-W Pix on Photobucket