The below pic is from the yoshimura site, with the yoshi 'Second Air Blind Plugs', i couldn't find anything like these in nz so used something else
picked up these bungs from para rubber, for $0.50c each, the pipe external diamater size is something around 12-13mm, they are hard plastic (eg things like bottom of steel chair legs)
Pretty simple job to do.
1) lift tank up
2) remove air box(1 bolt up front, 4 clamps holding on to throttle bodies, with 2 plugs and 3-4 hoses going in)
3) PAIR valve is a unit up front of frame, it has three hoses coming out of it, two top of cylinder head, one to air box.
4) Pull the plugs that go in to cylinder head(the one in airbox, already remove to get it out)
5) Plug the 1 holes, in the air box with the bung brought earlier.
6) Plug the 2 holes, in the top of cylinder with the bung brought earlyer. (1 & 2 in below pic)
You can stop here, or continue if you want to remove the PAIR valve totally, for this you will also need a resistor 18-22 Ohm, 5-10wat ($1 or so from Dick Smiths)
7) Remove the Pair valve (one bolt, and plug going in to it)
8) Put the resistor in the plug where pair was plugged in to. (above pic #3)
9) Turn bike on, make sure Fi light is not showing
10) Put bike back together and go riding.
With Pair valve is removed/disabled, this will stop your bike backfiring, lose about 2ish kgs of weight, and meant to give 1/2-1ish HP. The pair valve should be blocked before bike is dynoed.