Don't use the clutch lever with the choke lever mounted as shown in the first link.....it just doesn't provide enough leverage to pull the exhaust valves open (it does work if you are lucky enough to pull the lever while the valves are already open).
My bike uses a BMX brake lever, a cable I made, an extended lever for the shaft in the head...and it works fine.
Here is a link to my bike build. On Page 5 you can see my first attempt at the decompression using a Honda clutch/choke lever combination - it did not work as the clutch lever did not provide enough travel and the clutch would not release properly. I later mounted the small choke lever on a GSXR 650 clutch lever - and I discovered the small choke lever did not provide enough leverage to pull the exhaust valve open. On Page 12 you can see how I finally resolved it by using a BMX brake lever and extending the cam lever:
http://suzukisavage.com/cgi-bin/YaBB.pl?num=1358099938/0