Hey, trying to figure out how to remove the speedo cable from the gearbox as I am taking the engine out for an overhaul. Have searched about but couldn't find anything. The cable goes through a metal tube into the box. At the top of the tube there are teeth cut out and ay the bottom of the tube its bigger and is screwed onto the box. Everytime I try to turn it it will only turn around a1/4 of a. Turn and when I let go it goes back into its origiinal position. Any help would be appreciated. Baber.