Hi Paul, regarding the brakes. You say they are not responsive? The first thing I would do is give them a really good service. New linings, cylinders, flexes etc then I would fit a servo. The VH44 drum version is the one to use. This will make the brakes excellent. I have done just this and the brakes are as good as I will ever need. Will lock all four wheels if you want. When in good nick the standard brakes are quite good but need a lot of pedal pressure, the servo reduces the pedal pressure by about half. Disks won't do anything to increase the effect of the brakes, it just dissipates the heat better to reduce fade and allows water and dirt to be flung off the disk rather than gunning up the inside of the drums. Keep them clean and add a servo and you will be amazed!
Well...alright then, maybe just a little...