2006-2008 Polaris Snowmobiles FS/FST Service Manual., Page 54Get this manual
Maintenance 17To remove each valve shim, install the valve shim guillotine tool, PN: PW-47163, on to the cylinder head20Extract each shim with pick, or remove the rocker arm axle, then rocker arm, and then the shim
CAUTION
DO NOT DROP SHIMS INTO ENGINE21Measure the thickness of each shim removed from the engine and note next to the corresponding valve clearance measured in previous steps
18Insert the open-end of 18mm wrench around one of the rocker armsGently compress the rocker arm and push the valves downwards