Hey! Got a bit of first hand info here for ya if you want it...
I used to have the forks of my gl500 poking out by 1'4 inches because it look way cooler, I mean, with all of those insta-cafe racers is hard to ignore how good does our bike look like when messed with.
Went on a speed bump a bit too fast. Triple tree did a wonderful job digging into my front fender and bitting my tyre. Front brake lines and T connector of course dead. Triple tree took damage. Somehow I didn't bend the forks (that I can tell) but headlight lens snapped, all gauges broken, all fuses blown as a result of my spot lights relay smashing against my coils...and I myself somehow didn't fly off the bike. But my helmet did hit the handlebar, breaking the visor and cutting me, my neck had two very sore knots for about 5 weeks, and my back is still sore after 2 months. Im forgetting other stuff I had to repair...but yeah, there was more.
So in brief...for the love of God, don't shorten your forks that much. Specially don't do it yourself unless you know what's up.
Take em to a mechanic. They know how to shorten the springs (might want to look into how much a set of progressive springs are...as if yours are stock they're probably as good as butter by now) and add spacers, pre load and whatnot so they accomplish the following:
1. Shorten your forks by let's say to be on the safe 1 inch.
2. Make sure they're nice and hard so you don't end up in hospital when they depress deeper than the clearance actually have.
3. Make sure the rebound is not affected and you're still having a not so important comfortable ride but most importantly, safe ride. 4. Above everything else, they can advise you how changing the angle of your bike WILL affect its stability and put you in danger.
This all sounds terribly condescending but mate honestly I'm only trying to spare you from my own mistakes...