I think
the good book says adjust the lever end so there is 10mm between the knurled lock-nut and the end of the threaded part then about 5mm freeplay at the gearbox arm. Does that make sense? Probably not, if you're stuck let me know and I'll dig out the manual. Basically I believe you are you looking for about 5-7mm of slack when you pull the lever in before there is any effect on the cable as seen between the lever and stock.
It makes sense to me but then I've been out on the hit and miss all night.