For those that dont want to go down the path of the "bespoke shifter", i have installed a monkey shift kit from performatek and what a difference it has made. It is basically a reconditioning kit for the isostatic shift linkage that replaces everything that wears except for the bush at the base of the shifter. $150.00 well spent.
I also purchased the kit from Performatek. Luckily when I finally got a chance to get under the car to try to sort out the progressively sloppy and increasingly buzzy shifter it was safely in a garage 600 klms from me. The bush was fairly worn but the main culprit was the nyloc nut securing the rod, which was only fingertight and loose enough to undo by hand. With a grease re-pack and a couple of new O-rings plus a new nut the shift is now dramatically improved and the kit lives to fight another day. $3.75 well spent - $150 poorly spent