Get smaller grips. The iso grips are larger than most grips, moving the rear of your hand furthur away from the lever. Thus meaning you will have to reach further to reach the lever. If you get smaller grips, much like the stock grips, you hand is closer to the lever, meaning less you have to reach, and then you can just adjust your clutch lever accordingly.
You only other option is to look at sport bike levers and find a way to make them fit on your bike. A lot of sport bike levers are adjustable, I just dont know if they will fit in our perches. Good luck