ahhh peter posted while i was typing by the looks of it and seems like he is experiencing the same issue i was trying to adress in my post...

I just swapped the gen3 shifter into a rev 2.  I measured the levers, my findings are different to the pic in the link above.
 
Disregarding and spacers etc (which just move the entire lever assembly up/down, and doesnt effect the throw) the actual lever differences are as follows:
 
Gen3 lever has the cable attachment point 15mm higher, and is 10mm shorter in length.  The throw is significantly less and the knob also sits lower.  It feels great.  
If you are just after shortening your throw, you can DIY one easily with a piece of flat alloy and make it adjustable, and see how much shorter throw you prefer.  I can email you a pic later if you like.
 
Cheers