This was one of the first repairs i did to my bike as a it made changing gear an effort. What i did was replace the two pins that join the steel to the aluminium lever. All i did was grind off the ends of both pins and removed them, then drilled out to next size bolt (i think 5mm?). this was required as the holes in the aluminium were flogged at the ends. I then just wacked two high tensile socket head capscrews through and nyloc nuts on the end. I now have no slop at all and was a revelation to gear changes.