minityson - go here:
http://www.bakehead.com/minit_mods_page.htm
You will note that the link at the top of the page points to the original cagedmax solution for a HS-55 mod - I tried it with the HS-81mg and it too worked. It looks complicated but is really fairly simple to do. When you have a NON WORKING Losi servo - take it apart and look at how it works and the electrics - simple motor - circuit board - pot. The pot in the Losi servo is soldered directly to the circuit board.
Now the HS-55 OR the HS-81mg is EXACTLY the same except they have larger more sophisticated motors AND their pot's are connected using wire leads.
Everything else is covered in this little page!