My 49 1/2 ton had no parking brakes when I got it---only remnants of them. My question is how were they activated. One of the rear wheels had an arm attached to the shoe by an eccentric bolt---I assume for adjustment. How does the cable activate this lever? There must be something else missing and the shop manual is not very clear on this. The other side did not even have the lever. HELP! thanks to anyone who has been into these