I take it you have drum brakes,you will have to get the drums off first for a look before you worry about the h/brake adjustment,check linings for wear,leaking or seized wheel cyl`s,seized h/brake levers on the back shoes and your adjusters are nice and free,check if you have a lip on the outer edge of the drum and grind off so that you can get a good adjustment on your shoes,assemble brakes with copaslip on mating surfaces and adjust up till you get very slight resristance on the drums,forgot to say check your h/brake cables are not seized when you have the drums off,once the rear brakes are adjusted up then you can adjust your h/brake cables,think you remove the ashtray behind the centre consul for access to the nut,think it is 13mm,good luck
wickham
July 2010